Well, I began to expand into Croatia due to lack of suitable ways to expand elsewhere. I would have suggested Hungary to take the eastern part when you would have been back, but that polish inheritance was quite unexpected.
About that Swabia, I dislike that it happened, but I would not go to war over it with insane Poland and opportunistic France on both sides of me... Not to mention that sieging Rome is very hard thing to do.
One thing we could do is to edit it into an archbishopric and part of Germany, as someone might say Pope owning land here and there is rather silly. If it's edited now, it can be edited later similiarly if it happens to others. If it's not edited now, we won't edit similiar cases later either.