In my case i find that defense must be very high to start being valuable (moonvine pre evo gets rekt because her defense is too low atm) so i still prefer hp, but when assembling a team i consider their abilities, their skills and how they react together to clear everything in an effective way, for example a team with st paulia and di yu may have good total power, but that means nothing cause they hit pretty lame (specially di yu) and both of them are slow, so i consider speed (less than 600 speed for me is slow, full of rapid units :c) and actual efectiveness of every team rather than raw total power, because a lot of team just stack hp to boost their total power but that is useless when you need them to actually kill things. On a side note some1 in one post did the maths on the def vs hp matter, but i dont remember what post neither who did it