Oncall shift should be Tuesday to Tuesday

Maybe I'm taking you too literally, but I wouldn't want to have a handoff sync-up (or any meeting, really) on a Friday night, nor push that earlier so significant things can happen between sync-up and the actual shift in responsibility from person to person. Friday-to-Friday does sound good.

One thing I really liked in a previous job was a split daytime-vs-nighttime rotation. It was well worth a little annoyance to set up in our tools. One week you'd be the 'daytime' oncall for business hours (something like 9-5 Mon-Fri, though we might have tweaked those hours a bit; it might have been 10-6 or something). The next you'd be on call for the complementary time (5-9, weekends). You were on call for the same total amount of time, just smeared over two different weeks. It ended up being less of a burden to optimize your schedule for a reasonable response time, but operational work still got done. And in practice awareness of operational issues was not too hard to maintain between the two members of the split.

(I think the best thing, if you can swing it, is probably a follow-the-sun rotation where there are three teams distributed 8 hours apart around the globe, and they trade off 8-hour workday shifts. But a lot of uncommon things probably have to be true of your organization for that idea to even be on the radar.)

I've wished for a tech workers union for this reason. I don't care about pay, let the union say nothing about pay.

But let's align incentives. Any time spent fixing issues on-call is compensated 4-to-1. Workers may accrue compensation time, and any compensation time in excess of 20 hours is paid 10-to-1 when the employee leaves. The idea here isn't for workers to accrue and cash out comp time, but instead to give an incentive to the organization to ensure workers use their comp time.

Let's align incentives, what's hard on the worker should be hard on the owners and management.

Yes, 350€ (before taxes of course) per week. No additional compensation for responding/ working on incidents.

I would be interested in how response times are?

Mine is 15mins. So I have to respond and be in a incident call within 15mins.

We do daily shifts with a follow the sun rotation, makes it easier to handle persistent commitments and ensures a bad week doesn't all land on the same person.

My team has a meeting to hand off the on-call to the next person, and we discuss all pages we got during the week. Primarily two things: whether the page was for a good reason or not (good: our on-call person had an something actionable to fix. bad: non-actionable pages, pages because someone else's system was broken, false alarms, etc), and also whether there is something we can do so we never get paged for this again. I find it very effective at reducing pages.