How close should I keep my classes?

Hello, everyone. My main, Gladiator, is nearing 30, and I'm running into some frustrations leveling other classes, and it's kept me from going hard into it. Not that it's too time consuming, but I'm not sure when it's a good idea to stop and keep going on my main, since they all chain together.

For example, it would be really nice if I could make relevant gear for me at this level. To do that, I need to get multiple Hand classes up to the same level. But, I also need Weaver up to make gear for them. And in the process of leveling up these classes, I've now made a bunch of gear that my other classes are too low level to use. Rather than clog up my inventory, I should level up all the others at least some so I can get rid of the lower-level stuff. See where I'm going here? It ends up making me feel like I need to level up EVERYTHING since I want to craft some gear for myself now. But, I know that's not how people actually play this game. So, how should I actually be doing it?

Most people focus on one class as a time.

If you're not actually having fun crafting, then don't. Quests and drops should give you plenty of gear. You can also do some levequests to find some. Don't worry about throwing away low level gear, either - that stuff is all super cheap and can mostly be bought from NPC vendors anyway.

However, if you intend to continue playing Gladiator, you should try to level Conjurer to level 15. It should take a couple of hours, tops. At level 30 as Gladiator, if you have level 15 conjurer, you can unlock Paladin. You'll retain your gladiator level as a paladin but get access to paladin abilities. You'll want to level Marauder to 26 (for Mercy Stroke) and Conjurer to 34 (for Stoneskin) eventually, but those can wait until your paladin is higher level.

I presume you plan on maining Paladin. Level up Gladiator to Lv.30 and then level up Conjurer to Lv.15. Do the Paladin job quests. Now do the story quests and eventually level up PLD to Lv.50 and if you have Heavensward, get up to Lv.60. Do not worry too much about gear. They give you gear drops from quests, dungeons, and you can purchase gear in towns from NPC shops and market board.

Crafting is a big time and gil investment. Gathering is sort of the same way too. Do not touch these unless you are prepared for the grind involved. If you just want to do battle jobs, you can just focus on those until you make more friends in game to help you out with crafting/gathering.

If you want to level up other battle classes, you get an experience boost if you level classes lower than your main class. So please try not to level up your battle classes equally at the same time. Get one battle class to max level first.

I agree that a crafter class is not required for lvling up anyone. Dungeons drop excellent gear, you make enough money to buy decent gear off npc vendors, or you can do potd and ignore gear completely

I would not jump too heavy into crafting this early unless you just want to and enjoy it. You dont need to craft your own gear. You will be running lots of dungeons that drop enough gear to keep you going. If you end up with a really out leveled piece, you can check the market board and fill that gap. Given your main is gladiator, Ill tell you what classes you need:

Gladiator becomes Paladin at level 30. In order to unlock paladin however, you need Gladiator at level 30 and Conjurer at 15. Once those two things are done the quest will become available to unlock the paladin job. Every Job in the game has 2 classes that they can use cross class abilities from. For paladin that is Conjurer and Marauder. To access all of the cross abilities for paladin you need Conjurer at 34 and Marauder at 26. You dont need them at that level right now though. The most important cross skills are probably Foresight (marauder level 2), Bloodbath (Marauder level 8), Stoneskin (conjurer level 34), and Mercy Stroke (Marauder level 26). The 5th cross ability can either be Fracture (Marauder level 6) or Raise (Conjurer level 12) or you could just use cure (conjurer level 2) for some extra heals for soloing or something. Paladin has it pretyt easy though, you can level all the way to 60 and do just fine with Marauder at level 8 and Conjurer at 15. Foresight and Bloodbath are the only two cross abilities Id say you really want to get, and they can be gained in literally less than an hour. Get your marauder to 8, get your conjurer to 15 to unlock paladin, and then you can level paladin straight to 60.

If your inventory and retainers' space are really that clogged up already, you can definitely afford to slack off on the crafting and gathering classes, so you don't have to worry about hoarding materials as badly. You can take your time with those through dailies like Grand Company requests, leves, or eventually beasttribe quests.

Pre-50 for your combat classes, you should be able to make do with dungeon drops and quest rewards, and spend Grand Company (GC) seals on any improvements. Especially try to keep your weapon up-to-date; you'll have a much easier time holding aggro.
As you outgrow GC stuff, just trade them back in for seals if you need space. You can always buy them back much more easily later.

Once you're 50.. I recommend doing quests and FATEs until you're 51, and buy new gear from NPCs in Ishgard. Even though it's mediocre "white" gear, it's vastly better than any of the free stuff you'd have at Lv.50.
Once you outgrow those, you can convert it if it's fully spiritbonded, or sell it back to an NPC.