So, most Gitrog decks are designed to combo off, in my recollection. This appears to be using the frog for value to fuel basically a midrange strategy. If you want to do that, that's great, but it lacks a little bit of the complexity Gitrog is famous for. I think you know what I'd do if it were me building it.
On a more granular level:
-figure something else out besides
underworld connections. I think that's a nonbo in a land-saccing deck.
-Worm Harvest and Paetor's Council don't like each other.
-I can't put my finger on it, but for some reason I don't like
Overwhelming Stampede in this. I think I'd rather see something like
Primal Rage.
-I like Nissa in this. Animating lands can be risky, which is why I don't do it. But animating lands in a deck that can easily recur them if anything should befall them, that's pretty gangster.
-I also really like
Titania. I'd love to see a line where you have her out on a board where all your lands are mans and someone drops a boardwipe, getting you an army of elementals. And then you just play them all back out again.
-I suppose you don't have it, but I don't think
Avenger of Zendikar is optional in this thing.
-Dakmor
Salvage is also not optional, so I'm pleased to see it here. Silly question: are you just going to draw your deck or do you have a
plan for what happens when you draw your whole deck?
-Get an
Abundance. It's strong magic and perfect for this deck.
-I don't super love Mazirek.
-Cut Mazirek and use the slot for removal and wipes. Nine slots for that is less than half of what the deckbuilding template calls for.