Plus, with things like Zappa it's easy to go entirely serverless
Django + NewRelic for APM is plain magic
EDIT: Oh, and Celery if your use case needs it. Brillant
as a total hobbyist: why?
deploying a django app with zappa is extremely painless... its only issue is that you still need an SQL backend, as DynamoDB isn't really an option unless you want to kiss most of djangos values goodbye.
that would've been my take why you'd want to use flask... because there is very little value in django if you remove models, caching, authentication, permissions and more (that can't be used without external infrastructure) from the equation.
When your app is small and you got almost no users, zappa is great: your lambdas are lighting fast and you're in aws free tier.
When your app grows to like 200k SLOC and 50+ lines in requirements, chances are that it starts quite slow. Do you really want to pay for that?
When your load is high enough, well, aws lambdas become quite expensive even without zappa overhead compared to, say, EC2. https://servers.lol/ should say if serverless makes sense for any defined usecase.
Additionally, lambdas have hard restrictions (like 15 minutes limit) and sometimes it's a dealbreaker for you.
Frontend: Vue
Prefer Django, because it has so many things built in (authentication, other protections to build things super fast and not worry), many people call it magic but if you read the code, it's very easy to follow. [1] & [2] sites helped me a lot to remove the "magic" as well.
Prefer Vue because it is strongly opinionated, unlike other JS frameworks (i.e. React). Again, learning Vue allowed me to build things super fast and other having to worry about things like Gulp, Webpack and many more things that I don't understand in the JS community. Personally for me the JS community moves too fast for my liking and Vue has been a god send, especially with the help of Vue Cli [3]
Database of choice: PostgreSQL, because it is used by several developers rather than MySQL when building anything with Django.
Building realtime: I use a external service like Pusher or Pubnub, because they have generous free plans to get you up and running. But there is Django Channels if you don't want external dependency.
[1] http://ccbv.co.uk
[2] http://www.cdrf.co
[3] https://cli.vuejs.org