I will be reading the manga tonight, :) I have just read volume one and it seems really good, :) Btw I didn't notice about the names :o :P In the anime Kashiwa was not addressed by her name anyway, she was most of the time called senpai.
What I really liked about the anime is the soundtrack, I mean after the episodes it did get a bit repetitive to hear the same songs, but they are great songs that go with the mood that it is. Pearl Kyoudai really does some great compositions.
http://www.youtube.com/watch?v=uv2NyXxm4Ts :) Brilliant!
The voice acting was really good as well, when looking for pictures I heard a tiny bit of the dubbed version and it didn't sound TOO bad, but still I would rather watch the Japanese :)
By the way I thought the Masked Rider was amazing back in the day! :D