The Ar'kala seems to be missing a few things to be truly competitive with T5:
- 4/2 weapon slots (T5 has 4/3)
- No Lt Cmdr station (T5 has universal)
- Less hull (T5 has aprox. 5k more hull hitpoints)
I'd say the Ar'kala could easily be doable from level 30, until you hit 50. But -at- 50, you'd best invest in one of the existing Tier 5 ships, or purchase the Ar'kif Retrofit.
The standard Ar'kif is a nice "D'deridex alternative" for leveling Romulans. Going from flying "Escort-type" ships level 1-29, to a big, hulking, cruiser at 30 was a major pain in the gluteus maximus. Now all they need to do is add Science ship alternatives for leveling (and at endgame). Not to mention, major fixing to science abilities, to make using science ships more beneficial than they are currently.
I'm curious; Are the Quad Cannons capable of being used on any other Warbird, or just the Ar'kif/Ar'kala variants?