As suggested in the title, I have just installed FNV with all the dlc. Are there any recommendations for the most essential mods a first playthrough. Or which of the dlc's I should uninstall, because I know bethesda often provides overpowered items in their dlc's that screw over game balance.

Since its a first playthrough, I guess the best thing would be to just get bug fixing mods (graphic mods aren't as important to me because my computer isn't that powerful, a macbook running bootcamp.) However I heard that the lead developer created his own mod that makes some tweaks to the game to bring it closer to his vision. I wont be playing the hardcoe mode, though I appreciate a bit of a challenge, would JE sawyers mod be recommended for this playthrough?

Well Bethesda did not make New Vegas, so you dont have to worry about THEM putting in OP items in DLC that screw the game balance, you have to worry about Obsidian doing it, which they kinda did.

But, the base game + all DLC + Mission Mojave http://newvegas.nexusmods.com/mods/45104 is what I run. Mission Mojave being New Vegas's version of the unoffical Fallout 3/Oblivion/Skyrim patches.

I personally try to keep the game as close to vanilla as possible, but Project Nevada, found here: http://newvegas.nexusmods.com/mods/40040/?tab=3&navtag=%2Fajax%2Fmodimages%2F%3Fuser%3D0%26id%3D40040 , is a really good mod.