I tried to find players from the last 10 years to compare to Berggren. Roughly speaking, players in their D+3 ish year.
Emil Bemstrom, Djugardens (2018/19 D+2) 35 points in 47 games.
Jesper Boqvist, Brynas (2018/19 D+2) 35 points in 51 games.
Oskar Steen, Farjestad (2018/19 D+3) 37 points in 46 games.
Victor Olofsson, Frolunda (2017/18 D+4) 43 point in 50 games.
Oskar Lindblom, Brynas (2016/17 D+3) 47 points in 52 games.
Andreas Johnsson, Frolunda (2015/16 D+3) 44 points in 52 games.
Viktor Arvidsson, Skelleftea (2013/14 D+3 from first eligible) 40 points in 50 games.
William Karlsson, HV71 (2013/14 D+3) 37 points in 55 games.
Calle Jarnkrok, Brynas (2012/13 D+3)
42 points in 53 games.
Jesper Fast, HV71 (2012/13 D+3) 35 points in 47 games.
Johan Larsson, Brynas (2011/12 D+2) 36 points in 49 games.
Oscar Lindberg (42pts in 55, D+3) is the only player so far that never really stuck in the league.
In case Berggren keeps it up, Jakob Silvferberg (54pts in 49, D+3) is the only guy not named Elias Pettersson to go over 1PPG D+3 or younger.
So I'd say 40 in 50 is a good target that should project Berggren anywhere from a good 2nd liner to a solid 3rd liner.