yes I think early 2020 should be bitcoin soon to the moon, in my country there are many seminars on crypto on the student bench because many out there are interested in crypto, therefore many communities in my country about bitcoin / crypto, hear that I also feeling happy.
Usability and scalability are the main problems bitcoin is facing today, but I can tell you that a HUGE amount of development is going on behind the scenes of the markets and next time it does run higher, the whole ecosystem will be far more user friendly and a lot cheaper to use. then If people start investing in bitcoin and bitcoin based transactions increase, then this trend can breathe live in Bitcoin and price rise up again faster than 2017. remember Bitcoin has been announced dead in the last 10 years many times and every time it comes back. so buy now and waiting for the run.
What develop are you talking on behind the scene? You saying about Lightning Network (LN)? If you are referring to block halvening, usually it happen every four years so I wouldn't say that it is a development.
If we goes on another bull run, then perhaps we will experience bottle necks and the fees will be high, however, I think with segwit and LN we can reduced, but it doesn't mean that we will eliminate it.
Yes, there are a lot of bitcoin obituaries around, but guess what, those haters will continue to bash bitcoin but we're going to be find. 2020 though will be big but I'm expecting 2021-2022 will be bigger.