The fixed encounters on the way from monastery beach to Burz are avoidable,
although the3 slimes have to be lured from their spot to pass them with combat move.
Arnika can be reached at lvl 1 with full party, but below 4 is rather unlikely in normal runs.
The way to Fuzzfas is blocked by sevaral fixed encounters in the tree, some cant be passed in combat,
but are easily done with the trynnie patrols, add 1 level for that and 1 or 2 more for Barlone.
Import parties start at lvl 5 and optionally at Martens Bluff of Umpani Base Camp
but Kunar is easily reachable at lvl 1(pass the neutral hogar on Arnika Road with tincture of shadows)
while lvl 1 for Sadok probably requires constant combat moves through swamp and Bluff,
not to menion that you have to lure the swallower away from the exit of trynton.
Bela is also reachable at lvl 1, you only have to pull the golem from the bridge,
although it requires much luck as the way to Bela must be clear when you go in&out
and it makes not much sense without decent amount of gold.
X-ray makes this easy, and you can add the golem in the pond(the wakizashi is simply too tempting;)
Ferro also only requires the x-ray spell and enough power to kill the 6 spawning fire ants
the 2 rapax initiates on the bridge, and those 2 archers outside Rapx Courtyard,
which has several spots that are unseen if the guards are in default position.
(ensure to have no los on any target at the end of every turn, check with bow and long range spell)