The Forge Adept is decidedly worse than the Battle Smith, Artillerist, or the Armorer in combat and honestly, I would still take the Alchemist or Cartographer due to their utility. The Mavrick is even worse it focuses on improving your spell list but until 15th level you don't really get anything.
Maverick is bad overall, yeah. But I was mainly thinking about Forge Adept.
Forge Adept being worse than Battle Smith and Artillerist, I'll give you, but I don't think its by too much. Armorer? Current Armorer is... really, really bad. Level 3 is okay, but every other level is terrible, imho; this is compounded by the crap damage scaling upgrades and the Arcane Armor options all have individual issues. While there were a number of things you could do in 2014 to make Armorer really good and fun, the changes to the base class and the level 9 ability have actually nerfed this option really badly. If you think the Cartographer's utility is worth taking? Then I would suggest Armorer
below every other subclass except Maverick.
Alchemist honestly gets a bad rep. People that hate any kind of randomness really have issues with it, but frankly, I found that the potions
always have a use, no matter which comes up, and spending a spell slot works just as well if necessary in a pinch. The potion that gives you concentration-less flight is probably the trickiest one to use, and that's saying something when
flying is the hardest use case. The potions now scale with level slightly, you get more potions as you level, AND there's the fact that 5e24 potions are a Bonus Action now. And don't get me started on getting Tasha's Cauldron at level 15. That spell is AWESOME. The only real issue I've run into is a need for somehow getting a magical Alchemist Tools for fighting with, and I'm kinda annoyed that you don't get access to Greater Resotration.
Forge adept, on the other hand? You get scaling +x bonuses, which stack on top of things like Flametongue that don't normally have +x scaling. Extra Attack is standard at 5. Level 9 and 15 are direct damage boosters; simple, but that's kinda what you want to see. The subclass is simple, but its damage is decent, and that's what people who want a gish generally are looking for. The subclass does need a few quality of life tweaks, such as the new crafting discount methods and allowing the ghall'shaarat to work as an arcane focus, to bring it in line with the other subclasses.
The main benefit of Forge Adept is that, unlike Armorer or Battle Smith, all of its abilities synergize with the magic weapons you make, rather than against. The only real issue holding it back from matching battlesmith, i think, is that the damage, reaction, and extra HP from the Steel Defender is better than the +X bonus at low levels. At higher levels, I do think it evens out.