pgAgent has been my go to scheduling solution for quite some time. Sadly in 6 months it will be completely retired and the pgAgent UI in pgAdmin will be gone. The main reasons I liked pgAgent were:
pg_timetable has all the above features I mentioned about pgAgent except for the nice UI in pgAdmin. It does have a rudimentary UI here pg_timetable_gui which I haven't tried out.
Another scheduler I've been using and liking is pg_cron. pg_cron is a much simpler scheduler agent and is largely patterned after Linux cron except it can only do database jobs. When all you want is something simple to schedule SQL it hits the spot nicely. But it has no agents, the database is pretty much the agent. I was avoiding pg_cron in the past cause it was unsupported on windows and I needed something that would work both on Linux and Windows. So I submitted a patch to get it to work under windows, compiling with mingw64. I've only tested compiling against mingw64, but use it with the windows PostgreSQL VC++ compiled servers fine. There was another pull request added to make pg_cron compile under Windows VC++ which hasn't been accepted yet. Anyway in a later article I'll compare the two and also provide binaries for pg_cron on windows if there isn't already one by the time I get to it.