I donot know exactlly what do you mean by unequal server but Qlik Sense works fine with load balancing between slave and master.
It is possible to do load balancing with unequal server .
I'm currently load balancing across identical servers just fine.
I'm trying to find someone in the community that has real experience with unequal servers.
No, because in Qlik Sense you can control where the apps are synced to whereas in QlikView this is not exactly possible. In principle, it can work just fine.
I am working on multi node qliksense server installed on unequal servers with different configuration/memory. And it works well.