Whiskey, I knew you would respond to question 3 lol. You have some good points as usual, but.......it does look cool in game. I'm just experimenting at this moment and I agree, I would like it to be balanced as fairly as possible. Ok match some of the ships for me then. What would be the equal to the defiant in the Star Wars universe?
Well, the Defiant-class is technically a battleship, by virtue of the fact that compared to, say, a Galaxy or Sovereign (ST) class, it's very stripped down; there are very little amenities, crew quarters are bunk rooms that are shared between crew, and scientific facilities are very basic compared to the average Federation Starfleet vessel.
However, considering its maneuverability, somewhat diminutive size, and other factors:
The Defiant-class would be a heavy fighter or corvette analogue in SW; however, it's also a dedicated warship for Starfleet, so at a guess, I'd say that it's role would be defined as that of a frigate or light destroyer in SW, but it's size/design would define it as a heavy fighter or corvette.
Mod-wise, I'd make the Defiant-class a capital ship; while they did end up making quite a few of these ships, there simply weren't a whole lot built as compared to, say, the Galaxy-class. Part of it is the Federation's anti-war bias, and part of it was the design's usage as a dedicated warship was likely seen as fairly unnecessary post-Dominion War. There weren't a whole lot of very dangerous enemies hanging around, and the majority of Starfleet's vessels were likely deemed perfectly sufficient.
That said, it would probably be a somewhat inexpensive capital ship, by virtue of the fact that it strips out the amenities and comforts that would probably make a Galaxy-class expensive, as well as the fact that by virtue of being smaller it requires less raw materials.
Fun fact: in Warhammer 40,000, the Defiant-class would be considered a rather unusual fighter, but a fighter nonetheless. Mostly because it has active defensive shielding (40K fighter shielding tends to be more in line with navigational protection rather than a defensive countermeasure), and is FTL capable.
Note that it would most definitely not be the only ship to have such capabilities if a Defiant-class wound up in the 40K-verse; Tau Manta Missile Destroyers (which are actually attack craft/strikecraft) have extensive shielding and are also equipped with an (albeit innefficient, short-ranged) ether drive (Tau FTL system). There's also the fact that some Inquisitorial guncutters (fighter-sized personal transport; can accommodate 6 people) are Warp-travel-capable, so an FTL-capable fighter-sized warship would certainly not be particularly stunning to the Imperium.