Choice block is for gettting user’s utterances and match with your intents. If you put 2 Choice Blocks consecuitively, it’s like Alexa is waiting for user’s utterances 2 times without saying nothing for second time.
I’m not sure about your project, but IMO, 22 options for intents is enough for usual skills. Are you using slots? If you are in Voiceflow community on Facebook, this might be help.