1st time player looking for advice on Tech powers

So I'm a long time D&D player so I've got a good handle on the basic mechanics but I'm looking for some advice on what tech Powers I should pick. My character is going to be an engineer and I'm trying to be a DEX based combat and a utility support caster. As I understand it the at will Tech powers (cantrips) are much more powerful in this version of the game. Can anyone suggest a few that are really useful I might want to look into?