Thailand / Vietnam experiences please

[notjudgingjustasking]

Good evening,
We have booked flights to Bangkok next summer august then discovered the weather is quite unpredictable. We will be there for two weeks.
Was thinking of having 4/5 nights in Bangkok then flying to Vietnam looks very nice. Hoi an is currently my favourite choice. Is this OK? Is a week there too long?
We would still have a couple of spare days with this plan, kids very keen to see some wildlife how can I build this in?

It really wasnt that difficult. I think we only cycled about 650km in total as the coach picked us up mid afternoon each day and drove us to the next hotel. The most cycling we ever did in one day was around 100kms and some days we did a bit less. It was quite hilly though. Cycling up the Hai Van pass was a challenge as it was 39C that day. It was an amazing way to see the country.

I guess it’s not so bad when you are into cycling, unfortunately I’m a bit of a sloth 😂. Sounds fantastic though!