Have you thought about flying SQ between SFO and HKG and crediting to KrisFlyer? Assuming the flight timing works on SQ1/2, you get better service on the longhaul, and you can also credit JetBlue flights to KrisFlyer for your SFO-BOS runs. If you stick with UA domestically, you can get United Club access as a non-UA *G (but you’ll lose out on free E+).