Thank you for "listening" to my frustration a few hours ago. At 8 pm I tried again, and to my surprise my serger behaved again after re-threading for the 10th time or so (the other 9 times were this afternoon). It behaved weird before, so I do think I will have to buy a new one in the coming 12 months. But this at least gives me more time to think about what I want, probably a Bernina again. Anyone of you experience with the Bernina that has a coverstitch in the same machine? I do have a coverstitch, but might sell it in favour of 1 machine with two functions.
The result tonight: Jalie 2806 with gathered neckline.
I made quite a few Jalie patterns before, and I've never been disappointed. Good fit, good instructions (this is a very easy one to sew). Exactly what I expected it to be: an instant gratification project, though my serger made it not that instant.
For the gathers I used Belinda's instructions for a gathered neckline, if you want to make this top, do it her way. It's much easier to keep the gathers in place and evenly distributed.