Easy way for you is research website: transitbangkok. They show you how to go every where in Bangkok with all public transport.

Not sure about how henna artists work is at Asiatique.. but there weren't many of them there for sure.

The place is majorly sea-food-centric. There is a pizza place 'The pizza company' where we were able to find cheese only pizza. Otherwise, you can have lots of fruits and ice creams being sold there. Not many other options for vegetarians though.

I would suggest you take the BTS Sky Train (Asok is your nearest stop) and go to Saphin Taksim. Get off at Saphin Taksim and take the free boat shuttle to Asiatique from the pier. This will be much faster and economical, in my opinion. Otherwise meter taxi which might take longer because of traffic and probably more expensive.

Yes during evening time will be better

i realy dont know

Semplicissimo anche perché la barca ha l’intestazione del centro commerciale dove scendi la riprendi se torni dopo il tramonto sulla barca ci sono tutte lucine bellissima!!!!!

O guess up to 6 peoples

I didn’t see any boats other than the Asiatique boat stop, plus night cruises. Most boats stop just under the station and you can change boats there.