You know, I missed the most obvious answer to the Patricians wanting to distribute land. Just deal with it every time it comes up.
Slave societies dealt with slave rebellions every couple of generations for several thousand years without changing their economic model. We can deal with the Patricians bitching and moaning and needing to be put back in their box every so often.
Except the slave rebellions where always a very marginal threat, with only very rare occasions producing something resembling an actual concern.
And most importantly, slaves where not the segment that ruled society, nor where they the segment just beneath that one. Slaves where political and economically none existent (the chattel ones that is)
Chattel slave rebellions is a bad example, as it doesn't even make since to compare the two.
Noble rebellions and gentry machinations is a better example. And historically, the way empires dealt with them was :
1- give in, or butter them up to avoid the unholy hell that would be unleashed if not.
2- gather whatever soldiers are not rebelling or beg a foreign monarch to come save your ass, all the while praying that you still have a kingdom at the end of it.
Now Admittedly, noble and gentry revolts are not the best example, a those did own lands, which distinguishes them from Ymar counterparts in that aspect.
Hmm, Chinese eunuch coupes are a better example I suppose: the buecracy removing the uncoporative monarch.
The household slave revolts of the middle east is a better one. The slave buecrats and soldiers would up and rebel or replace the monarch if they feel he's not giving them thier just due.
Key part in all these, is when the most powerful, wealthy, or influencal segments of your society are pissed and making demands, antagonising them is idiocy.
Chattel slaves where non of the above, so naturally, empires can just squash them every couple of decades.