Yes. But oddly enough Bootstrap seems to have held up well none the less. Perhaps not ideal but if you did an average site in BS3 today you wouldn't be a complete fool.

Again, not ideal. But doable and certainly not fatal.

True, and we did upgrade from v2 to v3 in that time.

Also using angular-ui to spin up some internal tools quickly.

https://angular-ui.github.io/bootstrap/

If it were just me, I'd go with skeleton and style the rest myself, but with a larger team, a custom boostrap theme seemed to work really well.