Is it really so unstable?
No. It's actually just you. My wallet has been open 24/7. Just staking away. I never have issues if I restart wallet and need to sync blocks.
Everything seems to run perfectly on my end. getting about 10% a month staking rewards.
Maybe your Computer Clock is off?
I have not synced the wallet for more than 2 months and in order to mature the blocks, it is talking a lot of time. So we need to wait for blocks until it starts maturing? For some people, the blocks are maturing within minutes?