Haunted, the good answers (DMing your own game, ditching this fool for some sensible DMs in college) have been given. You wish to win an argument with a DM, however (try actually facing 3 groups of 4 goblins each in a day at level 1, with time to cast a CLW or two in between, and see if he still thinks you can't have more than 1 encounter a day at low levels) and for that you have chosen the correct tactic.
It bears saying: if up against a logic-impervious DM who thinks Core is balanced and Psionics (or Warlocks, or Fochlucan Lyrists, or anything balanced that's come out of splatbooks that aren't munchfests like Complete Divine) isn't, then the most powerful way to disprove that is to play a C.o.D. (Cleric or Druid). Noncore material will not be necessary unless you are going for pure overkill (Draconic Wildshape? Divine Metamagic?). So by all means, if you must win that argument, take you C.o.D. to town. Annihilate the opposition. Make the NPCs and other players scream "Oh no, it's C.o.D.zilla!!!!!" in badly dubbed English. Breathe radioactive fire. Knock down buildings. Then stomp out of the burning Tokyo that is the ruins of the game and swim off into the ocean, seeking a DM with some basic cognitive functions.
C.o.D.zilla's-eye-view of the DM.