Personally, I never feel done with projects, as there are always a few open projects, in which I'm involved in. (And typically 1-2 which "I should have finished year ago or so".)
First, what are good strategies of balancing between finishing past project and working on current ones?
On the one hand, concentrating only on current ones means that there will be a lot of "almost baked" project, in a form of partial results, never published drafts or papers stuck in the revision process. (Assigning second priority to something means that it is never going to be taken seriously.)
On the other hand, focusing only past projects would:
- look as if I were slacking off (also, as some past projects are from previous afflictions),
- have me stuck in working on projects, which are going to be "90%" for the eternity.
Second, being put in situation with constant (internal) pressure and no calm sense of finishing things (as even after polishing results, polishing a draft, going through a few rounds of revisions... there are still n-1 open projects), is there a way to feel accomplishment and not blame oneself when resting?
Here are a few tips that seem to work for me:
You can apply the Google 20% rule and allow yourself 20% of your time to work on projects that have no clear end point, which would include new ideas that you've just had or projects of the sort that you've just had.
New projects shouldn't become current projects unless they are close to finished or you make room in the 80% for them by finishing other projects.
That said, you need to evaluate the projects that you haven't completed and determine whether it is really worth completing them, apart from the fact that you've invested a lot of time in them. At some point you have to cut and move on.
Maybe you can write up the projects that are incomplete and see what you have in the end, and determine whether it goes into the 80%, the 20%, the bottom drawer, or the trash can.
Pick a few conference deadlines (or create a deadline for a journal paper) and work towards that to finish the work.