Having the Morgan fight would also be nice because of the Thrawn reference, it would give us an idea of what Ahsoka is up to early on. But I see why that is difficult Structurally.

Just throwing out ideas: Maybe this is a 2-movie edit?
One that intercuts Ahsoka with Mando, culminating in them finally meeting and working together at the end. (Opening fight scene of Ahsoka attacking the city would also need to be reinstated)
And then one that shows Bobas journey parallel to Mandos, culminating in those 2 meeting.

a bit less concise, but maybe it would give the audience more room to breath.