Unfortunately I don't think the poll is going to be entirely useful as there are far more scenarios than the ones you listed. However to contribute to the discussion: I play Normal only, unless playing with friends then we all go normal and champion.
I find solo play with a champion to be distracting, tedious and incredibly boring. I'm not a massive fan of the MOBA genre anyway which is why I have never been a huge fan of the champions, I think it distracts too far away from what AIW is all about. However in multiplayer its far less noticeable as you can speed through the nebulas much more quickly and you can split responsibilities so you aren't all staring at the nebula all the time. Still, the champion response felt like it took away the very advantage we were being given and since then I've just not bothered - its more hassle than its worth. I'd rather just get a golem.
The only things that could really change this are more nebula scenarios, shortening the nebula scenarios and (IMO) removing nemesis champions for something else (afterall the shadow frigates were meant to be just for us, to allow us to go into the nebulas - is there any explanation why the AI can't use or see them (the nebulas) considering they have hundreds of these things at their disposal?)
Whilst additional abilities and such seems like a nice idea it also makes me worried we'll have horrible balance issues as it becomes an all-in-one unit which you can adjust and modify on the fly (providing engineers are close by). It just doesn't sit well with me as we are either given a totally OP unit or you dial up the AI in some way that negates it to just make it a time sink while you're building something big.
However all that said, the beauty of Aiwar is being able to customise just about everything so i'm content with champions being turned off.