hehehe Ouch on the ex. If it makes you feel better, the thief is objectively the worst class in the game. Their dominant stat is luck, which really isn't used for anything in the game at all - not even criticals. It should have been used for running away in battle, but the algorithm in 1987 was messed up, so mine is intentionally to match it. :)
Same goes the White Mage with the Wooden/Iron staff. No idea, especially because she can use the Iron Hammer without a problem. And yeah, Elfland is the really grindy part of the game in my runs. Once you're past Elfland, you should be fine. Buy some "Tents" from the item shop and use them outside of the Marsh Cave to save before going in. And save at least one Fire 2 and maybe an Ice 2 for the boss of the Marsh Cave. Things should go smooth if you do that.
Also, if you're unaware of how the player order works in FF1, the players at the top of the order have a higher chance of being hit. The bottom two slots only have a 16% chance (IIRC) of being targeted by enemies, so the bottom two slots are where your mages should be. If people get poisoned or die, it will also re-order your party, so keep an eye on it after every fight.
As for the Spider, the only one I remember using is WutFace from Twitch. The Shadow, IIRC, is Kappa.
Glad you're enjoying it. And "Meme Mode" is *very* different in terms of story - once you know what the original story is like, it's worth going back, if only because there are cutscenes all over the place in Meme Mode. I believe there are nine movie cutscenes. :)