source: https://forum.cryptonote.org/viewtopic.php?f=2&t=192
You can pretty much forget about anything significant being added to BTC, unless there is a major change of leaders and philosophy. BTC in the year 2100 will look about the same as BTC of 2014. Maybe the side chains thing will go in, but even that seems questionable.
This is normal, and probably healthy. Technological progress often happens by leapfrogging, not evolution. The idea that "we can just merge the features" don't work once something because mature and (often well-founded) conservatism sets in.