Four things I'd like to see implemented

[Caimie_Tsukino]

Whistle System
The whole whistle system is cool, as it's supposed to be a reversed Inner Quiet for Synthesis instead of Quality, but as everyone's said since it's release it's currently much too double edged for what you're getting out of it. I'd really like to see some buffs or changes made to it to make it a little more enticing to use. I'm not asking for all these changes to be made (that would make it overpowered) but maybe just one would be great.
Change #1: Reduce all of the CP costs for it by 30-50%. It feels like a gigantic CP hog and all you get out of it is some minor buffs to Synthesis. you can get even more progress out of Synth w/o using it thanks to Rapid Synth II / Piece by Piece and for far less CP in the big picture.

Many crafters on this forum including myself had done some pretty thorough analysis on the Whistle System when it first came out. The system basically consists of 3 skills: (1) Satisfaction, (2) Trained Hand, and (3) Nymeia's Wheel (details please visit my Heavensward crafting guide Chapter 41). If you consider it this way, then (1) Satisfaction is already a CP-gaining skill, (2) Trained Hand's CP cost has just been reduced by half, (3) Nymeia's Wheel is already currently one of the most CP-conserving skills for durab recovery. So if we just "look at the surface", it seems there isn't any skill to further reduce CP cost (But that's not true! See below!).

In my personal opinion, I feel that the current Whistle System's biggest issue is that it is very luck dependent... On the sense that if you're unlucky, you will be burning a lot of CP for nothing. Firstly, you gotta be really lucky to have the W stack go down to 3 to retrieve 45 CP back into your CP pool using Satisfaction. If the W stack does not reach 3, that means you can only get back 30 CP at most from 2x Satisfaction. The WWYW system cost 36 CP to activate, and both Trained Hand and Nymeia's Wheel, despite their potent powers, cost CP. So at the end, if you are only lingering around W7 or 8 at the end of your rotation, you're pretty much doomed. You'd have spent 36 CP on WWYW, got back only 15 CP from a Satisfaction, perhaps spent another 16 CP on Trained Hand... You'd have only 1 chance (at W9) to push progress with bonus. And at the end, despite Nymeia's Wheel costing only 18 CP, there's unlikely to be any extra CP to be spent this way, especially when W7 or 8 means it only recovers 20 durab.

To resolve this issue, one can either (a) make those damn "Goods" pop up more, and make sure there's at least "Goods" to send the W stack down to 6 or lower in any rotation, (b) just as Kazzoey said, reduce CP cost for things. Now I mentioned above that (1) is actually a CP-gaining skill, and there's not much room to further reduce CP cost for (2) and (3) already. But one can still BUFF (1) Satisfaction. e.g. making it 20 CP instead of 15 CP. Alternatively, one can also reduce the CP cost of WWYW itself, from 36 CP to perhaps 20-ish CP. This will reduce the damage done when the W stacks are unable to go down to 6 or lower. Of course, this isn't the best thing to resolve the "luck" part. Because if you can't get the W stacks to go 6 or lower, than you really can't make the most out of WWYW anyway. But at least it won't HURT AS BAD.

Change #2: Adjust the Synthesis gain from +50 potency to EITHER +100/+150/+200 potency for their respective stacks, or +50%/+75%/+100% potency (multiplicative) for their respective stacks. Currently the bonus means nothing to people who use Rapid Synth as the gain is very minor, but this buff would make it more enticing for all Synthesis abilities regardless of base potencies.

I'm all for this. I'd say even DOUBLE the progress for any progress action during W9/6/3.

Change #3: Remove CP cost for Crafter Heart OR lower the CP cost and Good rates while making the buff permanent as long as Whistle is active.

This skill was dead from the start. I'm not even sure how to make it viable while not game-breaking. People who had tried it before find it really "shxtty" as they didn't get enough Goods to justify its usage.

Mainhand/Offhand
Probably a bit controversial but this is more of a gameplay change to help break up monotony and grind a little bit. Part of me is on board, part of me isn't so don't roast me alive if you don't like it haha! But I'd like to see a finer line of gameplay differences between Primary tools(currently used for 70/80 Durability crafts) and Offhand tools(currently used on 35/40 material crafts). One idea would be to grant certain abilities to be only used for certain tools. Such as Tricks of the Trade only being used on primary crafts or Muscle Memory only working on Offhand tools. Just idea, haven't really thought TOO much about it though. would like to see what everyone says about it.

Interesting idea, but unlikely to happen.

Second Quality Bar
This would be the biggest change, but I think it would be a great "end game" for crafters to push into a second quality bar after completing a 100% HQ craft. NOT to be another increase in stats, but instead the second Quality Bar would open up your overmeld slots instead. Pushing two quality bars for current meta, I think, would be nearly impossible but instead open up crafters to try and push their ability and luck to see how many Materia slots they can open up. Here's just a quick idea on how it could work.
-First, reaching 100% Quality will "lock" into place so you aren't worried about losing your HQ anymore.
-After reaching 100% Quality, you can activate an ability that resets quality back to zero (Current buffs, stats, and HQ is still locked in though!) and you lose one of your two open materia slots, and the other four are obtained through pushing the second quality bar. The reason for the ability is so that if you don't have confidence of getting any more quality, you don't have to activate it and still get your two freebie materia slots (but remember, using the reset causes your to lose ONE of those freebie slots so it's a gamble to get it back).
-The % by the end of the craft will be the chance you get a materia slot. The percentages also work sequentially (correct word usage?) meaning if you get 40% then you get a 40% chance to unlock a slot. If passed, then the next slot is rolled. If failed then no more slots will unlock. Kind of like the doors in Aquapolis?

Someone on the forum had suggested similar ideas before, and I think it is viable. Currently, it is very distinctly "NQ or HQ", with no middle ground. So previously someone suggested "higher quality bar = more materia slots". Your idea here is similar, except that it's a second quality bar. So it won't affect the existing NQ/HQ system, but will add another dimension of play. I'm all for this. It can make the game more fun.

Glamour Polish system
This one is pretty straightforward. I'd really like for crafters to wipe the stats from a piece of equipment and allow it to be stored into the Armoire for future glamour and safe keeping so that we don't have to throw away that pretty raid gear we worked so hard to get, only for it to be junk in the next update. They could even add a little bit of crafter gameplay to it somehow to make it a little more fun only if it wasn't a pain in the butt?

I believe any suggestion that has to do with allowing us to put more stuff into the Armoire is going to be welcomed by anyone. SE, please, let us put more stuff into the Armoire!