I like the deck idea! As a fan of landfall decks, it's nice to see others doing it, and doing their very own spin on it
In terms of your questions - creature count in a control deck can be quite low. I count 12 in your build, and I'd say that number is fine.
As for general critique/suggestions/feedback:
- I don't think you need the white. Making it 4C purely for the sakes of a Wall and a board wipe aren't worth it imo, and you should stick to Temur. That way, your land base will be easy to manage. Also, as someone who runs 3C (Naya) Landfall in Modern, 24 is the sweet spot for number of lands imo, and I would avoid using lands that forcibly enter tapped (eg Scry Lands), as you need them untapped to truly combo out with Mina and Denn.
- Consider
Lightning Bolt - they're not absolutely vital, but they are very, very good removal, and its in your colours.
- Consider
Remand (the price has crashed atm as well, so its the best time to buy/trade for them!) as you want to stall them whilst you assemble your win con, and it does both.
- Instead of
Wall of Omens, run
Courser of Kruphix - they're the best accelerator in the game for Landfall decks imo. I'd strongly advocate a playset if you can make the room.
-
Pulse of Murasa is very good in Landfall and even better in your deck as it allows you to
recycle the lands you've been using offensively/defensively. It might be too tight for you to fit, however.
- Another great card for this type of deck is
Atarka's Command, but they're a bit pricey.
I'm not saying you should or could do all the suggestions above, but it's just some tips and cards to think on that I've played with in similar decks and found to be very effective.
Hope the deck does well for you bud!