Since there are very limited answers so far, I'll add some.
At 45 these spawns will still be hard, but with your distance and proper player skills most likely doable (easier at 50+)
Krailos surface with fire walls! Good experience / mediocore loot (sometimes you get a lucky voodoo doll but thats it)
Liberty Bay Wyrms(Cave/mountain) will be good exp but dangerous if you encounter 2+. They are pretty much singles there though just dont walk around too much.
The old classic - Muggy Plains. Depending on how familiar you are with the spawn the xp can vary from really good to terrible.
Edron Vampire Crypts might also be considerable, probably not too great pre 50, but then with gfb+mas san it will for sure be a great spot.
Not sure about this one, but Hellspawns surface with energy walls might be doable, even though again risky. Just run east if you feel like you cant handle the amount and despawn them. Exp might proof to be pretty decent.~Eri