I like Rexler. I wanted to run him with predator and a HLC with a mini swarm but it so e point too many. I'll have to give him another go.
I would say drop the HLC I think the 7pts are better used than adding a single die to Rexlar's attack. I believe the math of adding a HLC actually decreases the value of predator on him, because it increases the chance of needing to use a focus offensively by having an extra dice to roll, and rather than rerolling 1(2) out of 3 dice now you are rerolling 1(2) from 4 dice which makes that reroll a tiny bit less of a boon. IE predator's increase in attack efficiency is decreased by adding the HLC especially when cost is factored in.
A real MathWinger I am sure has some numbers to contradict me(or maybe back me up) this was purely my general impressions regarding these two upgrades
I haven't run the numbers on this one, but Predator doesn't cost an action, so you'll get 1 reroll + your focus action. Its like having a soft Target Lock, and also focus, with 4 dice. That's actually really good. Unfortunately it costs a minimum of 45 points. It's not THAT good. Predator is, ironically, anti-synergistic with the PS6 Defender. If you get a free TL, then Predator is (for most scenarios) redundant.
Theres a reason why the pack contains both predator AND outmaneuver you know...