IMO, it seems that WWE has never truly supported a star they didn't make. With Brock, yes, he did get a monster push by the WWE, by going through The Rock, then The Undertaker TWICE, within the span of a few months, much to my chagrin, at the time.
However, Brock chose to leave WWE, try Football, then settled in MMA, where he fought at the highest levels, despite having no fighting experience, outside of D-1 Wrestling.
Brock is as much responsible for his success as the WWE is, and they know this. He isn't under the thumb of the WWE. I didn't like the comparison he made between himself and the great Bo Jackson, because there is only one Bo Jackson, but I think I got his point.
He is athletic enough to perform well in any athletic endeavor he chooses to. He has an iconic image, to where if you were to design a Super Soldier, in your mind's eye, something like a Brock Lesnar would appear. Flat top, trench knife tattoo, scowl, and everything.
I'd love to see Brock in a new Universal Soldier movie. Book it, Dana/Vince!