I really like Maelstrom Archangel here because she's also a strong reanimator target for the entomb / pod / sneak attack axis of decks if you support those too. (Best line I've seen with her in my cube was Sneak her in, connect, drop Ulamog who now won't die EOT.)
Nexus is a strong card but will only be of interest to someone who is already super deep on a 5C goodstuff deck, Maelstrom will be interesting to anyone who has ways to cheat creatures into play regardless of color(s). Obviously if you generally expect decks to pay the listed price for everything, that'll be less relevant.