The spawns you already mentioned are really good! But as you mentioned on a populated server they are crowded indeed.
Grimvale has gotten 2 alternatives in the winter update you might want to check out!
Those are located
a) just south of the edron orc cave
b) on cormaya
If you do the quest connected to them you also get access to 5 daily bosses which can drop the wolf backpack and you get a foxtail amulet as reward. For information on this check http://tibia.wikia.com/wiki/Grimvale_Quest/Spoiler#The_Curse_Spreads
As Kincaid already mentioned Elder Wyrms in drefia might be an option. The EK might get beaten pretty badly though. If you decide to go there start off slow and dont get swarmed.
For Lizard Chosens the spawn in Temple of Equilibrium is really nice. It is easily accessable since all you have to do is start Children of the Revolution. The rooms really benefit you as a two vocation hunt as they are already nicely clustered for you.
Another spot worth trying might be War golems! There are some spawns with varying difficulty you could test your luck on. Start off slow, lure 1-3. Depending on killing speed you might wanna drop some e bombs/walls and run them over to speed it up. If you feel comfortable start luring some extras and see how it goes.
I have not tested this, but maybe baby rosh could be a viable option for a duo at this level. Just keep in mind that garlic necklace is essential there and don't lure more than like 4-5 at that level.