1)Wraith (light, lot of damage works with everything and with turian havoc solider whilst using havoc strike it automatically reloads but otherwise not the fastest reload speed)
2)N-7 Crusader (its fun and best for poping guardians heads)
3)Graal Spike thrower (can do a lot of armor damage so good for krogans take little s**** out with melee and bigger with this also pretty good accuracy)
4)Disciple (staggers, light and good damage enuff said)
5)M-27 scimitar (good to spam and ok damage fun to use with marksman skill)
6)M-300 claymore (so much damage, ok accuracy but one shot and long reload)
7)N-7 piranha (fun when camping with team but such a bad aim so only for small closed maps)
8)AT-12 Raider (good damage but terrible middle/long range aim and same as piranha good for small maps)
9)Reegar carbine (i just dont find it fun to play with but it is very op)
10)Geth plasma shotgun (its just ok but had good accuracy)
11)M-22 Eviscerator (used maybe once wraith its just better version of this)
12)M-23 Katana (what is this?)
but this is just ones opinion
also OP you still need to make assault rifles, SMG's, pistols and maybe best melee characters 
i cant comment on venom since i dont have it...