Many people have problems managing their inventory. There are two reasons for this. 1)Limit of 80 spaces. 2)The game is built horizontally. Meaning you need one set to ws in, one to tp in, one to cast cure, one to nuke, etc etc.
Here are some things that are VERY easy to implement that will help many people out.
There is a very common number in FFXI. That number is 8. 8 elements, 8 days of the week, 8 items in the trade window, etc. Things that go along with this number are:
8 Elemental Obi's
8 WS Gorgets
8 WS Belts
8 Elemental Sachets
8 Elemental Grips
8 Elemental Staves
etc
Some of these items take a lot of effort and work to get (all 8 trial staves, either magic damage, magic acc, or avatar for example). Now as a mage, having all 8 obi's, all 8 staves, and all 8 grips, you are now down 24/80 inventory, over 25%. That's a lot of space.
I propose you create an npc that if you trade him all 8 obi's (8 spaces in the trade window so no problem there), he gives you a rainbow obi that works for all 8 elements (The Twilight cape is the same thing so they could easily make an obi to do it). All 8 Sachets = Rainbow Sachet, all stats +2, hp/mp, and occasionally absorbs magic damage. All 8 ws gorgets/belts = a gorget or belt that works for all ws's. all 8 element damage +6, element acc +1, element casting -14% = one staff for all 8 elements. etc etc.
This turns 24/80 inv into 3/80. MUCH easier to work with.
The coding for this should be relatively simple and will help the strain on many players, especially mages.
Now another idea that WILL draw even more attention to Limbus, Dynamis, and Abys would be an AF combo system.
Allow someone who has the AF+1, AF2+2, Emp+2 of any given piece, trade all 3 to an NPC, and you get a new piece with all the stats from all 3 pieces. Since the AF2+2 already breaks the previous amount thought that can be put on a gear, this shouldn't be a problem. If for whatever reason it is, then take the highest def of the 3, all hp/mp/attribute stats (adding them together. ie AF+1 has str+5, Emp+2 has str+10, new piece has str+15), the emp+2 set bonus, the af2+2 trial bonus if done, and then let us pick 5 of the other stats on the pieces to custom make our own.
This may not be as easy to code if there has to be custom things done, but would greatly reduce the amount of inventory and gear swaps needed. It would also be a new draw to older content to try and get the best gear possible.
Just some ideas that I think will make the game better and help out inventory issues since it doesn't seem that we'll ever break the 80 number due to ps2 limitations.
And another Mog Sack would also be wonderful, but sadly wouldn't help the 80 restriction to our gobbiebag. Some of us have over 80 pieces of gear for one job ;;