I'm starting to feel a little overwhelmed with Warhammer releases

The Siege Assault Battle Group for Horus Heresy went on pre-order today, and I wanted pretty much everyhing in it so it made sense to get. The problem is that at least one of the new units in it is a resculpt of a unit (or units)n I already have, and I want to replace the old ones with the new ones because they're cooler. But the sheer amount of stuff I effectively have to endlessly repaint is overwhelming me, especially with the yellow colour scheme I'm going for. It's a slow burn of a project, but I don't want to have to repaint them again in 5 years time if they redo them AGAIN. Sure those models are 10 years old now, but I've definitely not had them for that long. They are pretty stubby though...