Blue gives you Murmuring Mystic downshifted to commonand Talrand, Sky Summoner for more token generation and Tetsuko Umezawa, Fugitive will make your tokens harder to block
Tidus, Yunas Guardian Tidus, Yunas Guardian is another commander whose usefulness in his deck will be entirely decided by the accompanying cards, but its easier to imagine what that could look like
This deck is loaded with monstrous dinosaurs like Wakening Suns Avatar and Apex Altisaur, so cheating those into play for only four mana is likely to shift a game wildly in your favor
So, in short: while ramp and draw are both amazing, Id prioritize whichever helps you make your land drops
This means even if someone tries to break through your defenses, you get a backup plan to survive another turn cycle