Ryuta

Randomus is not that hard to take down unless he can set up trick room. Just make sure that you can get rid of Reuniclus ASAP. Your team and reserve are looking good to take on him but you might want to bench Noivern and switch to Zoroark for this fight since the field effect give psychic type move gain a rock type so Noivern gonna get wrecked(Trust me on this Noivern is my ace too). You might want to try Persian from my playthrough oddly enough he wreck Randomus team pretty horribly(Techinician+Fake out+Assurance = RIP Reuniclus). About Leavanny, I don't think it's not a great idea due to how

@Kalaylay His hawlucha is pretty fast but it's not that bulky beside you have gale wings Talonfalme that should be able to one shot it with the acrobatics+boost of Big top arena you fight him in(I have it on my playthrough too and it did for some reason). If you have problem may be you can train up your starly, it can hit pretty hard and can survive one or two hit. Another thing you can try is to catch Noctowl on Route 2. It's pretty bulky good at taking hit and it has access to movepool that counter Samson team pretty hard. Also I suggest you bench Yanmega for this fight because even though