Another well written piece!
Labour sold themselves as being able to create "a partnership in power" at the last General Election, but the whole dynamic is rigged. The way it is structured means that the partnership is similar to that of a parent and child. You can see Welsh Labour are wanting to create space between the two govs, but if push comes to shove, parliament can tell the Sennedd to sit on the naughty step and withdraw power.
I think the only way around this while keeping the union is for England to have their own devolved parliament. There can still be a UK-wide assembly, but this should operate similarly to the EU where each country can still have a fair bit of autonomy.