Also wanted to say that once I switched to Arrange mode at the Corel entrance to Gold Saucer, I toggled the Randomizer on and have been using it ever since. I liked the mechanic a lot, but the whole aesthetic of it is a bit wonky. I would maybe give it a different name instead of "Mister Smile" and clean up the text box display for the randomizer. Basically I just always took the +10 or +15 buff if it rolled one, and always took Luck if it rolled over 5. My whole team having quality stats with mid-to-high Luck has payed off pretty often in fights. I guess this didn't polarize my characters identities as the hack intended as much as it is supposed to, but I was able to shore up any low stats with all the crazy buffs on equipment and materia.
Another thing is I didn't really think that the troll jokes on relevant item locations added to the game's quality. I mean, yes it's kind of funny to find the Sense Materia, or to get regular junk (A Heavy Ring and that Spear both seemed really out of place and random, as they are both fairly common items that don't hold much relevance) for the Mythril. I would suggest just giving the player something cool & interesting, maybe even objects alluding to the vanilla item. I don't really want to ever play a hack and feel trolled or ripped off for going to investigate something that's normally worth doing in vanilla. This also goes for the Curator challenge boss in Shinra Mansion. Defeated it and was aggressively informed I'm not getting
strawberries? Could easily just give the player a Key Item that's just a badge of honor that serves no purpose outside of 100% completion. I guess opening that chest counts as part of the completionist route? I can't say cause I'm not a completionist or a speedrunner.
I think it might also be relevant to remind the player, maybe in various shopkeeper dialogue, that selling high AP materia like Sense and getting a new one is very relevant to staying on curve with being able to pick up items and equips. I would even go a step further to discourage the player from selling their armor and weapons and take this route instead, as the stat buffs of each weapon continues to be relevant as the game progresses, despite their attack power being outclassed. Have not touched the Throw materia this game, but that's also another corner case for not selling your weapons to pay for ether, hi potion, and tent.
Stuff like the AP grinding weapons and the Precious Watch are kind of so late in the game that they are only relevant if you just somehow failed to grind your materia for the whole game. These are fine I guess, but as an experienced player I was making sure to grind AP from the very beginning on each materia.
Speaking of AP grinding, I wanted to point out this thing from Vanilla that carried over to NT and has been on my mind forever; Vincent and Cid are the only two characters with a Double AP weapon that has a combo slot. Everybody else has singleton slots, as do all the armor. Is there any way to switch around the slots on any given weapon, maybe give each character a double AP weapon with a combo slot? I say this as it is very relevant to level up some of your support materia, and kind of pigeonholes the player into using Cid and/or Vincent during that period of disc 1 while you're still maturing your materia.
edit: Also, terribly sorry if this is an unpopular opinion,
but I just hated the Dark Cave sidequest. Everything about it felt like I was just being subjected to the remnants of a separate, discarded hack (maybe the original frameworks of NT?), none of it was relevant to the story or made any sense, none of the events were explained or even speculated upon by the characters outside of them all saying "hmm... something weird sure is happening!"(this was particularly painful to go through, as there easily could have been more elaborate dialogue, such as the during the Amalgam fight, literally anyone could have said something about how jesse/biggs/wedge were being used in the cutscene. Also the Amalgam was a really weird fight where Barrett's Drill Arm made it no longer difficult), and basically the only point of it seemed like showing off some unused reskinned enemy models (speaking of, that weird reskinned rainbow thing in ancient forest is just hideous...). But all in all I just did not enjoy any aspect of this, and felt like the item drops added in, two key items and the mystile, were just thrown in arbitrarily to make you not feel like you just wasted a bunch of time running around midgar. When this event was explained as a sidequest, I was really not expecting that it would just be a weird recycling of the start of the game, but rather a unique sidequest with it's own events.