What shapes do you all like for big concrete transition? Best I can really do is some 5050s and standup grinds, some frontside ollies, etc and I was thinking my big krooked gonz sweatpants (90s shape like the dane) with 169s would help but it appears to not be giving me any better lock-in. Are the huffer or phawt shapes fun for transition, or would the square-er tail of the 90s shapes be better?
I would be inclined to say any board with a longer wheelbase is usually better on big transition of any surface, be it bowl, ramp or whatever, as you are usually going at faster speeds so having a wider and lower stance makes skating it a bit easier for most normal people, even if it is only slightly longer (like the huffer / phawt) at 14.75 but others often go for the 15" as a solid ride too, most common on some of the bigger boards from "all rounder" type companies (Antihero, Black Label), with not so many options the companies that focus more on street / curb skating in that range. That is not to say that there aren't good boards (with longer wheelbases) from those companies too, but there might not be quite so many.
As to tail shape, it is down to what you feel more comfortable on, as some people will prefer a popsicle or rounded tail and others will prefer as much board under their feet as they can get, both options working very well for those who are more used to it, along with the other way round being quite weird or uncomfortable if you are not used to it. Getting used to some of the tails on Santa Cruz reissues, or even on a Black Label Auby 80s shaped deck was a struggle for me, but a more mellow square tail on other boards from Black Label or Antihero were easy to get used to.
The only thing I would add (not deck related) is bigger wheels, 58 to 60 mm being way easier on big stuff too, which help with the lock in factor. That is not to say that smaller wheels are no good, but for me, something around a 56 mm is good for everything too.