Hi,
Yes it's posible at some point, the idea has been on the todo list for some years now but there always just seems to be endless amounts to do just for the C64 version!
Certain concepts such as the 16 colour palette and particular features of the VIC-II are quite tightly woven into the current system and trying to squeeze in support for another platform would likely break a lot of existing stuff.
So yes it's possible but would require a great deal of work and most likely need it's own separate version rather than making the current tools more flexible to accommodate it.
I once owned a plus4, I liked it and it is definitely something I would like to do.
ps. Thank you for your support, it is greatly appreciated.