All somewhat rough choices however the only totally incorrect one is the one without the life gain
W for a 1/1 (So far, so good.) 2W for a 2/2 (Pearled Unicorn, but not horrible.) 10W for a 5/5 first strike creature (Wait, what?) 1U for a 0/3 (Eh, but bearable.) 3U for a 0/6 (Getting pretty bad here.) 11U for a 6/6 islandwalk creature (Wait, what?) B for a 1/1 (Muck Rats, but okay.) 4B for a 3/3 (Looking a little worse here.) 12B for a 5/5 creature with pseudo-fear (Wait, what?) Those ultimate mana costs were paid out over multiple turns, but if your creature died before hitting their highest level game over, tons of wasted mana, yikes
Indoraptor is only playable in eternal formats like Vintage, Legacy, and Commander
In three-plus-color decks, you'll almost never or rarely play all MDFCs and should pick and choose MDFCs from the "always play" category that are most impactful and best support the theme of your deck, rather than just running them all
This is especially true for Commanders that want to cast massive spells like Ovika, Enigma Goliath