You know, you're right. It's just that Morrowind's invasion plot was far more subtle than what Oblivion's and Skyrim's plots are. It wasn't so in-your-face.
Agreed. The invasion was more of a silent revolution with forces growing from inside the island.
I think an invasion can be done as many times as possible, so long as its done in a unique way.
For instance, we haven't really experienced things like being part of the invasion party, or being born into an invasion.
I think those plots would be interesting...rather than watching an invasion begin and get dismantled.