I spent some time with TW:Warhammer and had a blast. Wasn't sure what to expect but IMO it was the best since the original Medieval.
Offworld Trading Company looks interesting, I have it on my wishlist and will pick it up for the right price. Similarly, Stellaris is also there, one day I'll get around to it.
Still on the fence with HOI4 - I gave up on HOI3 in frustration so I might pick up IV in next year's winter sale.
Thanks for posting the link!
I recommend you wait till they come out with a collector's edition which will contain all the DLCs. The other reason to wait is that their base game is usually very flawed and require patches. A big complaint of HOI IV has been the AI. Also, just be aware that if you found HOI III too complicated, HOI IV will be even more so. That company is known for adding more stuff in the next iteration and not really known for streamlining the game for the next iteration.
I didn't find HOI III complicated (I have a three year long WiTP:AE campaign going on so I'm ok with complexity), more the AI. I found the pathfinding to be terrible, trying to conduct my version of Barbarossa and the AI had my units going all over the place.
Definitely wait on that one until it's a better price.