Flooding the board with Tarmogoyf tokens makes it just enough of a threat on its own to be a respectable commander
Raging Battle Mouse's cost-reduction ability doesn't change the mana cost or mana value of any spell
Xolatoyecs main function is untapping any of your cards with counters on at the end of turn, effectively providing most of your merfolk with vigilance and untapping any lands bestowed with Flood Counters, freeing up mana for counterspells and reaction-based play
You search up Plains equal to the difference in the number of lands, put one in play tapped, and put the rest into your hand
Many of the best equipment and equipment payoffs simply weren't in print at the time, like Colossus Hammer or Sigarda's Aid, and ones that were in print (Stoneforge Mystic, Puresteel Paladin) weren't included because that's how precons roll, I guess