Well this is just my thought but maybe you need a stronger weapon the enemies always go after the one that deals more damage and you should spam singularity,force hammer and that purple gas skill( forgot the name)
1. Even though singularity is used to attack groups it works well to get attention of just one person,people dont like getting knocked back
2. Force hammer is a good skill cause it damages and taunts at the same time and if you upgrade it enough its stronger than your highest critical hit
3. The purple gas skill is excellent because it can damage the person as if your shooting them( its slow but really gets their attention
4. Like I said stronger weapon=more attention so you should look in the auction and buy a good weapon stronger than the one you have now and possibly buy a damage enhancer implant( reallyexpense though,crazy people) and have the aggro pouring in.

And if you dont believe me I stole attention from a level 30 engineer so yeah or look at other's postings and follow theirs its okay my advice isnt perfect