I've yet to fly the A220 (why didn't they call those planes A221 and A223?), but from what I've been reading online, they've got wide seats and lots of overhead bin space, enough for one rollaboard per pax. I would love to see AY replace the E190 with A220.

The fact that AY crams more seats in their A321s doesn't mean that they don't need smaller planes, too. As long as they aim at two flights per day to all/most Euro destinations, they will need a bunch of small planes to cover thinner destinations.