Going where the players lie is best, if you need players. I ask do I? Right now I think my game is sustainable with referrals. In ten years or twenty? I cannot guess.
Your card flipper is almost a full tabletop virtual environment. The goal to be independent of others and control what is created is probably best.
Roll20 seems like someone else wants to own your stuff. Epic Table is dependent on a programmer as a side business.
Voice is the most important. I probably could run the games in Skype sharing a desktop and bringing up images. Then w/ a second PC or sheets of paper, have my notes on the unknown.
More is nice, but the cost is both learning curve and added don't work. We have seen the first case where Epic Table simply lost a host server for authentication and caused us a scramble.
Spending a half hour to figure out how to make the friend requests work to simply start (AoE) is not my idea of fun. That will only get worse as PC and OpSys age.
CardoFlipper (tm) is the most desired platform to spend on effort to build, effert to learn and effort to create content. The world is not an oyster, it's a castle with walls are high and thick.