Clone before you do it... but I think the chainguns are kinda fun if you are going to go toward the commando line.  There are times you want to conserve ammo by using a rifle or spread the love with a shotgun 3 rounds at a time.  But if you have the cash for a lot of ammo take all the skill points you have been chucking into rifles and put it in the chaingun section.  You can still use rifles and all that,  but over all, the chainguns can cut anything down faster than than any rifle can.  Think like Hicks and just keep one shotgun "handy... for close encounters" in an open slot. 

If someone you usually hang with has Rage, don't bother getting it because rage does not stack.  Just remind me... er... him to hit rage for you and stay close to m... uh, that guy while it's on.  If you solo a lot or don't team with me very much, put lots into that one.  It's fun.  It's almost like having critical hits with every shot.  I seem to get a lot more crits when I turn it on too.

Reflective armor is always better than Motor Assist.  I kind of miss mine now that I've gone to Stealth armor because it blocks those howler things from stunning you.  The only armor better than that would be the graviton armor in the next teir toward commando.

-Shock