Demigod is the least complicated and advanced of the MOBA games. Smite is simply LoL in a third person perspective. Demigod is different in every way. You have creep upgrades, tower upgrades, flags to hold and a limited number of "champions" (Demigods) and several maps. Demigod did some genuine innovation on the MOBA genre while most other games just copied DotA.
That being said, Demigod is probably not gonna be liked by a hardcore MOBA fan, and the netcode is absolutely awful and the support is nonexistant. It's a "play with friends" game. It could've become something, but the netcode issues killed the online community at launch and the lack of support made sure it stayed dead. It got a very short resurgance when it launched on Steam, but quickly became dead again. Now there's maybe 1-2 custom games going at any time, compared to maybe 30 in its heyday.