I own it on both Xbox one and PC through Origins and I haven't noticed any weird bugs. The only one I noticed (and made me laugh) was when one of my paddle fish escaped the fish tank and was "swimming" around the cabin in ME3 which was the xbox version.
They are all great I try to mix up squad combinations for unique dialog too but they all kick ass in my opinion.
Is Wrex dead or no? Because if he is dead then sabotage the misson but use a paragon speech check so he can survive. If you do this with Wrex he will know but if you do it with the other guy he will never figure it out and you will.have both krogan support and salarian support. And if wrex finds out you will have to kill him.
Talking about the original posters cat6 heavies they have sheilds like cerberus guardians and it makes the fight much easier when you use pull to yank their sheilds away and use a shotgun to take them down. Very useful when you have the skill tree maxed and have it split into two projectiles.
Make sure you have full loyalty for everyone
Tali as tech specialist
Garrus or miranda to command second team
Samara as biotic specialist
Mordin or Legion to guide your crew back to the normandy
Garrus or miranda again as diversion team leader
I like to take Thane and Miranda with me at the end to warp all the enemies barriers
They arnt so bad if you use pull to yank their sheild away.
Are you playing on PC or on a console? If you are playing on console I would just wait. If you are playing on pc I would get the games downloaded off or Origin and pay the bare min subscription which is 5 bucks a month and with the sub all the DLCs for the trilogy are free.