There are no stat requirements on equipment in DKS, just level requirements.
The floating oranges are beholders.
In D2:ED (playing a warrior) I put a couple points into Potion Efficiency, but didn't bother re-investing after getting the battle tower and unlearning my skills. I didn't learn it at all in DKS.
I also wasn't impressed with Thousand Strikes in D2:ED, though mostly because I did so much damage with regular melee attacks that I didn't really need an extra attack. I don't know if balancing changes in DKS would make me reevaluate that opinion, though, as I have not played a warrior again (yet).
Mana Efficiency comes in handy. In D2:ED I put 5 points in so I could summon my creature and still have enough mana left to be able to use the healing spell (level 1) if I needed to. In DKS I'm playing a ranger, and it helps with the active ranger skills (since I didn't put any stat points into spirit or intelligence).
In DKS I found the creature helpful even with just the basic parts. IMO he is most helpful with a mage head. Some people (especially playing mage or ranger characters) like the fighter head for its Fatality skill bonus, but I tried it for awhile and went back to a mage head.
When you are done in Maxos temple you will get access to Sentinel Island. Your first encounter there you can mindread to go up a level, so the higher level you are (I made it to level 22 in the fjords) the more of an experience bonus that will be. You don't need to get to a high level, but it would be better if you got to a new level before entering, to get a full level bonus.
