Bangkok Airways flies from BKK to LPQ, its a small airline but has decent service and seats. I would take this over the Laos Airline anytime.

The monks early morning alms processions is the reason to be there. There is no exact timing except that it happens at the break of dawn. Avoid the central main street as it is more like a zoo particularly in the weekend where Thais tourists are in town. To avoid the crowd, head for the street next to the river bank.

Take trip to mount Phousi for a view at dusk is pretty nice then go down for the night market which is right at the base of the mountain.

One thing in LP, things flows slowly and you may be surprised that you don't want to do anything else but take in the pace of the locals.

I am more of a dirt rolling backpacker than a highend traveller so I don't have recommendation on the lodging nor restaurants.