Are there any mods out there which does not reduce XP gains for killing lower level enemies? I'm hating the grind and spending too much time killing without any rewards.

I understand you can gain exp through the console but would rather gain xp going through the game

No. But you can camp at certain places to get higher level spawns (like the water node).

Are the water node enemies tougher (give more exp) than the enemies in fire node? Creatures spawning in fire node were giving me less than 100 exp per battle. That was at Lvl 9.

If you are using the Co8 mod pack, the encounters on the world map scale with your party

Lordy yes, sleeping in Deklo Grove can be brutal.