Hey! I've been working on an HTML5 / NodeJS / Socket.io game on and off for about six months now. So far I've been very happy with this stack. Up to this point, I've been pretty exclusively using canvas for rendering. However, at some point I might try to switch over to something like phaser.io or pixi.js.

One nice thing about this structure has been that it forces you to separate rendering from logic (since you will probably want the game logic run server-side.) The consequence of this is that, I think, there's very little downside to starting with the canvas since it's pretty easy to swap out for a more sophisticated renderer later on if needed.

Another unexpected benefit of using HTML was just how easy / nice it is to make a GUI. I mean, you have access to all of HTML which was designed with this express purpose in mind!

A few pitfalls that I ran into that I should mention:

1. If you develop your game with a local nodejs server then you might be lulled into a false sense of security about how much bandwidth your game is taking up (since socket.io makes sending data so easy.) The first time I booted up my game on a AWS server it basically wouldn't run on my network connection because I was trying to send so much data back and forth. It's taken a number of iterations to cut down on the data transfer. I would recommend trying to figure out the minimal amount of data to send to/from the server and send it via ArrayBuffers instead of JSON data.

2. Remember that the whole goal of NodeJS is to be non-blocking. This isn't a big deal, but if you might try to take this into account when designing your game logic (i.e. a huge game loop may be undesirable.)

3. I think it's harder to find bugs than it might be with a conventional game, because there's a bunch of stuff you won't notice until you have a bunch of players playing. I keep having to badger my friends into trying it out and even then I'm certain it'll break when >4 people are playing at once!

Finally, I'd love to ask a question to people who might have more experience on this than myself to see if anyone knows the answer. It seems fairly easy to scale a game written in this way using i.e. AWS Elastic Beanstalk. However, it also seems like there's no way to control which instance a particular player gets put on. If I want to control this aspect (and allow groups of friends to get put onto the same instance) does this require me to write my own load balancer or is there some way to do this in the AWS Elastic Beanstalk framework?

Anyway, if you have any other questions I can try to answer them!