I think this plan is alright and can work but the only thing that concerns me is the direction you take this in for uniqueness. For example, your plan doesn't cover a lot of the fine details of what these rounds look like at certain points you show cards so I assume that there may be some deck building elements but I don't read any. I think the parts that I gather in which this is a tower defense that rewards players with synergy and having plants living long offers an interesting take that if done correctly can be unique and fun.