You are not the first one who is hating this low level epic campaign which starts with mindflayer spelljammer ship fighting hordes of enemies... I had made a thread about that
http://forums.larian.com/ubbthreads.php?ubb=showflat&Number=672140&page=1However, this focus on low level stuff is more like a WoTC thing than a Larian's fault. The notion that everyone is ludicrous weak and over 99% of the world population can't even kill a house cat using a spear is being enforced by WoTC since the late stages of 3e. Back on 2e times, the page 96 of Domains of Dread mentions that Strahd is a 16th level necromancer but before the fall of grave, he was a quoting the book "In life, he was merely a 5th level mage" and the book mentions that 5th mage is something of "mediocre skill" many times, the book itself downplay mages bellow lv 10 many times. Other books for the realms of dread also recommend starting at lv 8.
And if you look to the highest magical campaign ever, on Netheril : Empire of mage, most NPC's are about lv 15~25. Karsus himself, the strongest one is a lv 41 magic user(arcanist pre fall /wizard post fall)
Paladins, one of the most popular 2e classes only started to be able to cast spells at lv 9.