which place do oyu feel comfortable to level up at? i prefer places like, that one place where you save Agrias , and those plains where you save algus (cant remember the names right now.)

I prefer to level up at Mandalia planes. The enemies are easier, and it's easy to surround them and break the enemies down and accumulate.

I also prefer to level up in the deep dungeon, no reasons though, just prefer.

I like places that are harder to fight in, like the volcano place where clouds sword is, or the poison swamp. Also the deep doungeon is sweet before you have everything in it.

I use mandalia planes or zigolus swamp if i want to to some major leveling up, or if i want to use the poaching trick.

mine is the first place you fight (Mandalia Plains)

old skool - Mandalia plains
then Barius Valley
and finally Deep Dungeon

Mine would have to be the deep dungeon. It's all the levels and a great mix of monsters to train with. But you definately have to save before each level.
I also like the poison swamp.