I went back and cleared out the last 4 Act 4 Battlefields. (In the GOG version, the key you find after going all around the act looking for different chest does unlock level 6).
As I suspected, it wasn't really worth much. I gained a whopping one extra level, so I'm level 34.
I unallocated all my DK's skill points and I put them into the following Summoning skills in preparation for Act 5:
- 10 points into Extra Radius. That gives a big enough radius to cover an entire dungeon level from the middle.
- 20 points into Level Upgrade. I haven't settled on a final distribution yet.
- 11 points into Extra Skill Slot
My plan is to have one summon (probably the Raanaar Skeleton) be a tank and the other (the Demon) will be a Mage giving support. The skeleton will probably stay at level 1 because I need an item mule, and he would be too expensive to level up compared to the others.
What happens in act 5, if I then decide to put points into additional summon skills? Will my Paladin's skills stack with or override the Death Knight's skills?