I haven't found a manager that works, but I've yet to have the opportunity to test the one Savok posted about. That one seems to rely on custom profession names though...
I've forgotten to plant a couple of times too. I dunno why the dwarves can't simply remember where the field was and plant a new one next year with the same crops. I use the same area over and over again anyway, they're not goldfish are they?
The amount of farmers I have varies wildly with the amount of farmers I get through immigration. I turn all peasants to farmers unless I have critical shortage in some other field, but outside of that I leave professions alone.
Between paging through all those lists and flicking jobs on and off and trying to remeber which job goes with what profession, or simply making do with what I have, the latter option is a lot more appealing.
If the dwarves would just starve to death quietly instead of tantruming and wrecking the whole infrastructure in the process, things would balance themselves up, nice and quiet.