SE Asia tips

[Jamon]

Currently planning a 6 week sabbatical with DH at the end of the year which currently looks like this;

NYE Hong Kong (staying with BIL)
Fly to Hoi An for 5 days (been to Vietnam before but didn't make it here)
Fly to Siem Reap and see Angkor Wat (3-4 days enough?)
Fly to Sihanoukville 4 nights at the beach
Fly to Luang Prabang - how long here?

That's where I've run out of steam. I want to see more of Laos - Vientiane for e.g. Any tips on what else to do or see in Laos or Cambodia would be much appreciated! And how to travel around - we're trying avoid buses but trains planes are fine.

My advice-
Check weather for hoi an in January - may be wet as it is dry there in the summer.
Angkor wat - you can buy a three day ticket or one day - so I would consider spending more than 3 days there unless you plan to visit temples every day. The three day ticket is valid for a week. The town, market and night market are nice for a stroll and a temple free day.
Also consider P Penh - palace, museums, killing fields etc. you can fly from SR to PP but car and driver is also possible. Think we paid about 60$ four years ago.
Vientiane. - good for monuments, wats etc, but quite small city so probably only need 3 days.
Have you considered the place with the jars (name escapes me)?

Thanks for the tips! It's so hard to know how much time you'll want in each spot

I'm not sure what the jar place is ?

www.lonelyplanet.com/laos/northern-laos/plain-of-jars -