I know this may sound crazy... But, go 1 less Ronintoadin as it can't banish another Ronintoadin to Summon itself anyways. As for replacement of Triangle and Ronintoadin if you are interested in any:
Aquarium Stage: For general battle protection since WATER is pretty uncommon type to go against.
Aquaactress Tetra: It searches Aquarium Stage, but not only that it is a target for Swap Frog to dump, and it is target for Surface and Salvage.
Testudo Erat Numen: This guy is a good flood gate to yield your opponent from summoning most threats. It is also a target for Swap Frog to dump, and it is a target for Surface and Salvage.
If you decide to run any of these Level 1's I've mentioned... Also run One for One as an option to get them out.
Or since you are running Nimbles and Swap Frog... You can throw a few Nimble Angler for Swap Frog to dump and a few more Water Nimbles for Extra uses of Nimbles field swarming powers.