If someone who does subclasses/array-likes or so (e.g. like Stefan
Hoyer ;)) and is interested, and also we do some
teleconferencing/chatting (and I have time).... I might be interested
in discussing and possibly trying to develop the new indexer ideas,
which I feel are pretty far, but I got stuck on how to get subclasses
right.

I am off course very happy to discuss this (online or via teleconference, sadly I won't be at scipy), but to be clear I use array likes, not subclasses. I think Marten van Kerkwijk is the last one who thinks that is still a good idea :).