While I love the universe, I'm too ar(/u)tistically challenged and too much of a poorfag/cheapskate to play mini. So my exposure is largely Dawn of War 1&2(fuck 3), and extensive reading on 1d4Chan(though I have started the novels with Horus Heresy).
I had check out the last few years, so imagine my shock in discovering GW finally stopped fearing the 42 millennia and started moving the story forward. Robby had final ended his emporer as he is impersonation, and is starting up an emporer as he was impersonation. I'm still getting caught up, but I think the new Primaris bolters look cool, I like how they are treated as greener than Orks. I could see the space Marines evolving into using Primaris as rank and file, with veteran old school astartes being the elite veteran corp. I do like that they just aren't immediately the super awesome Better Marines.
I'm sure there are those resistant to changes, and that always opens things up to getting Nu Warsed. However, for a long while there had been all of these totally Galaxy wide threats that never have their shit together. The sleepy Necrons, meandering Tyranids, natal Tau, squabbling Chaos, even more squabbling Orks. The disorganized, selfish, backwards Imperium has partly survived on their enemies incompetence.
I don't know if they are going to push things that forward, but I like the idea of a few hundred years of the Imperium getting their shit together, so that they can be prepared to face, or participate in facing, some of these threats. Roboute cleans up the Imperium a little (just enough), the diversity is our strength commie weeb Tau become a larger power, the 'Nids arrive in full force, and the other factions wake up or quit jerking/killing each other off.
I think it's better than Abbadon leading his billionth crusade before going back to the eye to pinky and the Braining it over again.