So from what I've tried so far:
Build 2 txt make the phone much more snappier somehow - and snappier in a good way. Since this is still my main and only phone, with more intensive apps it still works well.
Build 3 txt also makes phone snappier, but less, IMO - Build 2 seems to perform a bit better. Also build 3 seems to have the overheating thing, because as I checked CPU got very hot (~65 C).
Boot image seems to have helped, but I haven't properly tested yet. Also I did put in the lib files too without any problems.
Thanks for all of this.
Sent from my Xperia M2 Aqua using XDA Labs