Laos forum

Hello everyone, my girlfriend and I are traveling Laos for a month from mid-march to mid-april. We've done quite a bit of research, on this site and forum and beyond, but we wanted to ask the gracious members of the forum for further advice.

A bit about us, we're in the backpacker budget range looking to spend about $1,000 USD/person for the month. We're very active, looking for exciting treks, and a mix of on and off the beaten trail stuff. We're going to hit up the usual stuff, unless there's something to be avoided in favor of something better. I drive motorbike, and can speak Thai and a bit of Issan Laos so we're not afraid to go off on our own.

Ok, here's the places we've keyed in on. We'd appreciate if you'd recommend a better place, or think the place isn't worth the stop.
Slow boat to LP, north to Nong Kiaow, Phongsali for a trek? (heard it's less touristy than Luang Namtha), Plain of Jars (1 day), quick stop in Savanakhet, Pakse, motorbike loop through Salavan, Sekong, and Tad Lo, before ending with some chill time in 4,000 islands.

Suggestions? We would consider flying north to South to avoid the long bus from VN, but not sure if it's necessary because we're stopping off to see Savanakhet. Thank you TF community!