There's something about manually writing and copying over TODOs to the next month that makes you really question if you still need to do it, and if you do, gives you a reminder that you still haven't done it.
I use a few basic markers copied from standard bullet journal, which work well as a dot can be promoted to all the others. A dash "-" for informational stuff, a centre dot "·" for a task, which turns into a slash "/" for partially done or a cross "X" for done, ">" if I carry it forward to the next month and "<" if I copy it into the future log (I have pages at the front for about 4 years of future events, 3 months per page). I also have a leftmost column for the date when something needs to be done or for meetings/events.
Surprisingly, even when doing a whole page of notes on something, it's not excessive to leave an inch margin, and sometimes you want to star a key point or attach an action point market.
I've got really used to this way of journaling, and appreciate the ability to do different things, like calendar views - such as 36 week views with one page for weekends and the other for mid week - which are great for planning holidays, weekends and significant events.
I never really got into the monthly reflection aspect, but I do like doing that around end of year and other inflection points through the year.