I've attempted multiple games now and i can't plan anything because one moment i'll have positive incomes then the next my pops have reshuffled(?) and now i have negative incomes?? It snowballs and i'm basically fighting a constant war of trying to balance my resources. It's not specialists jobs stealing my workers either, i'll have no new buildings and all of the sudden my resource incomes have completely flipped and now i have a constant battle of trying to normalize them. As far as i can tell the planets aren't automated either but the new population system is so baffling i honestly can't tell--why are they constantly splitting and reforming.
TLDR: The game is terrible about allocating pops, you have to micromanage or adapt one way or another to get anywhere.
For more-or-less "normal" empires, there are basically three obvious ways to manage jobs currently. They can be over-summarized as A) Don't build enough jobs, B) Build only exactly enough jobs and manage pops, and C) Build more potential jobs than you need but turn some of them off, managing active jobs.
A) Don't build much. Keep a healthy surplus of civilians on all developed planets; so basically all jobs are worked all of the time with plenty of pops left over. This really only works well if you use one of the weird and/or exploity builds that generates much of your resources from civilians. This is probably the easiest option, as it extends the way you play the game with just your homeworld at the start; but it limits your output of anything civilians don't produce (e.g. alloys in most cases) and only really works well with certain specific builds. It may also still require some additional manual population movement micro to optimize (but probably less than other options.)
B) Be extremely careful to balance everything out by building only exactly what you need. This may require play with a calculator and notes or spreadsheet alongside your game client, at least until you have a good feel for a build. E.g. if you're building a city district for science on one world, queuing up a consumer goods district and some trade to transfer it on other worlds; and transferring the right amount of population to each of them just as they are completing. This does require a small reserve of civilian jobs, but only on one planet which you then transfer exactly as needed. It may not be viable in a multiplayer game where you can't pause whenever you need to.
C) Build at least a bit more districts / buildings / jobs than you need, but control available jobs by spending a lot of care in reducing available jobs. This requires spending time and attention fiddling with the jobs on planets. It may not be viable in a multiplayer game where you can't pause whenever you need to, although it's probably faster than B). All pops are working "real" jobs (with no significant pool of just civilians in the empire), and generally are working on planets that are highly optimized for what they're doing.
B) and C) will probably give better results than A), but require more attention and micro from the player. I've been tending toward C) myself but that's partly because things have been broken enough that some of the strats for B) are probably the result of bugs that have been or will be patched out.
Edit to add: Technically, there's also option D), which is invest in storage expansion, keep a large buffer of everything, and don't sweat the swings up and down on a monthly or other short term basis. This is inefficient in cost and resources, as you by definition have a lot of resources lying around unused at all times; but should be viable in unpaused games as you're more or less just watching the annual average resource bank account level shift up and down slightly and compensating occasionally.
Late Edit: Let's call E) "Wide enough to be able to hyper-specialize planets for everything, and have enough additional Trade to support moving it all around." This is technically a variant of C), because you typically will need to build a few things that aren't in the planet's specialty and then turn the jobs off. For a "normal" empire, this assumes at least eight decent planets with reasonable pops each; at least one each for energy, minerals, food, alloys, consumer goods, unity, trade, and science; so this may be a mid-game strategy at the earliest for many. Depending on optimization, you may want separate planets for each flavor of science, taking your planet total up to at least ten. (And you will probably want additional science planets beyond that.) The advantage is that you can pick planets that are particularly good at one thing; the disadvantages include empire size, possible loss of bonuses when you have planets good at more than one thing, and how long it takes to get running.
