go for stamnecro, magsorc or stamblade those are the best classes in the game
I just have to LOL. This new noobish player thinks that the MagPlar is the easiest class to play at the lower levels when I wanted to solo Public dungeons due to its class AOE kit. (I'm only CP 225 so far) My Stam classes are all under class level 50 right now, and they seem to take much longer to kill things and I still die on some Delve bosses, or other AOE types of situations that I do not have problems with when I'm using the MAG classes (Sorc, Templar, and Warden) that seem to melt the NPC's when I compare them to the STAM classes that I have.
Note: I gave up on MAGDK, MAGNB, and MagCro as they did not seem to be working out like the others. so I switched to STAM on the DK and NB. I just gave up on the Necro as I wanted a Magcro and its just not there IMO.
I'm sure that there is a lot to this game that I still need to find/figure out, and I may be able to unlock some skills and abilities at higher CP and skill points that I do not have available to me now.
Edit: I'm slowly forming the opinion that I have had in other games that the "best class" is the one you like to play.
I know you're getting the generic answer a lot but it is true: Every class can clear all the solo content, and it is actually quite easy. It just takes experience, level, and gear.
I can recommend good "beginner" classes but you will eventually grow into a better player. My best advice honestly is to choose a class you like the look and play style of and learn that one. Choosing a class based on how easy it is to solo that you end up hating is just a waste of your time and enjoyment.