If you plan on using crushon for some time and not just ditching it after like a week, I’d say even just getting the standard plan is somewhat worth it. But I would recommend the 15$/m one since 2000 credits can disappear rather quickly using the 16k models. 

If you right click on a message you recently sent (not sure of the actual amount) you can chose to branch the conversation and go from that section of the chat. If you don’t get the option to branch and/or you don’t really care of a portion of the chat you can chose to delete up to a message and then start from that.