A nice looking collection and some interesting conversions/scratchbuilds. (I have a spiderman action figure in my bitz-box myself that one day might be turned into something chaotic

)
And i also think of steeling your valkia idea.
And do you have a better whole body picture of the demon prince?
But i think your paintjob needs some work. The colors you choose are great and give the models justice, sadly the same can't be said about your execution. Especially
HQ units would benefit from a more clear paintjob. Some areas need a touchup where paint isn't smooth(jump pack) or spilled over the boundries(wings and typhus armor for example). Some flat areas need some washing and also highlighting would add much needed substance to some of the larger single colored areas.
But you are on your way