Been doing A TON of research over the past 6 months getting ready for when availability opens up for flights for my finance's and my honeymoon in April of 2018. Have plan together but want to get everyone's opinions about everything and my options.

So heres the breakdown:

Points/miles we have-
Chase Ultimate rewards points: 280,000
United Miles: 110,000

Flights needed-
SFO-SGN
SGN-NRT
NRT-SFO

Our plan is 10 days in Vietnam (fiancé is Vietnamese, part of this time will be visiting family), and 6 days in Tokyo/Japan. Goal is to leave SFO on April 15th, 2018, SGN to NRT on April 25, 2018, and NRT-SFO on May 2, 2018.

We want to be sure to fly at least business on each leg. And would love the opportunity to try as many products as possible for fun. So based on availability and ease of booking this is what I'm thinking as a goal to book as award tickets-

All booked through united:
SFO-SGN - EVA Air via TPE (160k for 2 business saver tickets)
SGN-NRT - ANA (80k for 2 business saver tickets)
NRT-SFO - United (160k for 2 Polaris business tickets... assuming the new 777-300er will be on this route by then)

So what does everyone think about this plan? We're short about 10k miles/points, but if we don't earn those in time when I book them I'll just buy them from united.

For the first leg from SFO-SGN I had planned on trying to get the SFO-SIN-SGN on Singapore (and have a 15 hour layover in Singapore, explore for one evening)... but after their recent devaluation, and the risk of the chase points not transferring quick enough for the availability on Krisflyr, it makes me nervous.

Any other thoughts?

Thanks for any help!!