You mean SpS? They are ok at solo pve, horrible for any kind of kama/raid/group. Decent in high level pvp. Basically spam hydro blast and frost bolt to kite.... cancel is also useful in pvp, you will figure it out, it's not complicated.
Spellsingers can be more than just "terrible at groups" if they learn teamwork and mana management. I am essential to our kama groups, and I can make a small party level around 30% faster when I'm around.
Not to mention my quick savior spells that keep party members from dying, sometimes at the cost of my own life but heck, I like it.
As for leveling at 46, alone, try to find a place with undeads where your solar flare one-hit them. There are plenty of them, one I recall is just outside Aden, between the castle town and the cemetery.