Beta and Delay:
There are problems with beta, but they have improved a lot compared to alpha.
I suppose beta is also an older version of light years from the finished game.
Especially since they were seperated developed, the graphics bugs and fps drop i think only beta problems. I expect that the full version will be in everything ok.
The reason behind the delay was obviously the console versions, unfortunately but this was an expected thing. Blizzard did not release diablo 3 all platform same time. But a little bigger company...

Gameplay:
My main problem is that I do not have enough weapons or skills.
I do not feel the customizability. (Now I'm not thinking of painting here.)
Assasin or sniper I like to go best because I have the feeling yes here a set of tactical packages can be varied.
Crusader is very boring and slow.
Psyker very interesting and easy to learn but he cant hold.
Need more weapon more skill more custom option.
But this is a beta experience! I think full version there are some surprises.
I hope New turret option for heavy gunner and puri+radi weapons...even more.

Basically, the gameplay is fun but the enemies have something to polish.
There are very op or very weak.
Of course this is a matter of time because it's just beta.

Ideas for future:
I would have to wait for a couple of turns, especially on the radical and Puritan side.
For example: They catch and get out of jail, but you must associate with a chaos sorcerer who is also a prisoner.
Your decision is killing or cooperating with it.
If you deal with it and get it out in exchange, it would give you a weapons or help some kind of picture later against the other chaos warband. Fire against fire or chaos against chaos ...
If you kill then maybe Imperium would give you some extra.
The strength of the warhammer universe is depth.
Everyone can find his own path.
Wh40k games failing because almost only play Imperium.
Tons of races but in almost every game there is only a imperial road...
The Inquisition can give you the space to make a choice the Puri or Radi a much more personalized way.
Where you can join together with other species to reach our goal.

I hope puri and radi Weapons, skills (I liked some chaos warp skill for pshyker or crusader chainaxe maybe assasin dark eldar blades or dark lances weapons.)
More depth to story more warband and races.