After that I'd work on improving the lands, focusing on mana-fixing lands that enter untapped since this is a 3C deck and our commander requires all 3 colors
14 Voracious Hydra Voracious Hydra takes one of the key mechanics found in most hydras and simply does it better than the rest
To say nothing of the confusing way that Humble effects interact in layers and other power and toughness modifications, many players avoid using Humility-style effects
Lets take a closer look at this underplayed card
Whatever you need, Green Suns Zenith is able to find it at minimal extra cost
Later in the game, you can have a greater toolbox, with different exiled creatures that can provide card draw, bounce, removal, or just size