yes, I am afraid that it is the 4 Old Firm games that attract the TV deal money.
I think the best we could hope for would be a 14 team top league incorporating some kind of split....and, I think the split would have to be a top/bottom 8-6 to make sure the actual champions would be decided on an even keel with even fixtures.
That would also give a bit of leeway/wriggle room/breathing space for clubs such as ours....and a better chance of being in top section following a split.