I doubt this would cripple RDW. They can still Light Up The Stage and cast instants on your turn. With Chandra you still get to play the best of your two draws that turn. Frenzy is crippled, but they'd still be drawing two cards a turn for when they eventually blow up the Frenzy. And three're still the problems with Rule of Law: it's a dead topdeck, and it doesn't impact the board the turn you play it. Remember RDW kills your mana creatures. What if you don't have an accelerant on turn 1 and by turn three they have two Pyromancers and a Lavarunner? You could easily die (especially since they can still cast burn on your turn). Furthermore, if you don't play Rule of Law on turn 3, its potency drops quickly. By turn 8 for example you would much rather draw Hydroid Krasis than Rule of Law. We could play some games if you like, but I'm unconvinced.
Otherwise, I played some games with Brad Nelson's Simic ramp/Nexus deck:
https://www.mtggoldfish.com/deck/2081407#paper Boy, the deck is bad. I have no idea how he got it to work. I literally had no way to interact and things like enemy Hero of Precinct Ones would just chump block forever. Against an Abzan tokens deck, opponent missed lethal, but had Trostani, and I had no way to remove it while opponent played March into March and walked over me. Nexus was just a 7-mana cycle quite often; it's possible I generate so much mana I can cast a planeswalker and Nexus on the same turn, and that indeed happened once, but with no other action in my hand Nissa just animated another land (which didn't even do anything against my opponent's 4/4 Gruul Spellbreakers backed by Domri's Ambush) and that's it.
The sideboard was also awful. Where is the interaction? Four Cerulean Drakes and 2 Ripjaw Raptors are nice against monored, but what about every other deck?
There are a few other things about the list:
- Leafkin Elemental was surprisingly good. I thought it's just there for elemental synergies, and to some extent it is, but it's able to tap for 2 mana surprisingly often even with the board not stalled. The point is if you play creature after creature, opponent is not going to be able to remove all of them unless he has a sweeper. With cards like Cavalier in play, Leafkin Elemental is barely a target. Then together with two Llanowar Elves or maybe a Nissa land, and you tap for 2 mana.
- However, Leafkin Elemental does not tap for blue mana. In a deck trying to cast Mass Manipulation this is a liability (and Brad still has 3 copies of the UUUU spell in his sideboard ...).
- Cavalier synergized surprisingly well with Tamiyo. It was also a solid body: 5/6 reach is basically unkillable by damage-based removal.
- Aether Gust was surprisingly bad. I was expecting a 2-mana removal spell, but then I realized it lets the opponent choose where the permanent ends up. If I targeted anything actually worth killing, it's undoubtedly going back on top of the deck, and then Aether Gust just stalls for a turn.
Overall I do not think Risen Reef is the way to go with the deck. It was OK, and impressive when it went off, but there also aren't enough elementals to really make it shine. It's not just Llanowar Elves and Hydroid Krasis here, things like Voracious Hydra are necessary to interact and that's not an elemental either. Maybe Brad has better ideas, but I'm sticking with the more conventional Simic ramp decks for now.