Preference level for me:
Segwit + dynamic block size proposal (as discussed so far) > Segwit alone > block size increase HF alone > BTU emergent consensus. The latter is risky and definitely not adequately tested.
Preference level for me would be (current moment of thought - I reserve the right to change my mind):
Segwit + dynamic block size HF > block size HF > BTU > Segwit SF. The latter introducing a two tiered network system and a lot of technical debt.
Although a quick and simple static block size increase is needed ASAP to allow time to get the development of the preferred option right.