There are 3 major timelines in Tenchi Muyo!. There is the OVA/Ryo-ohki timeline, the Universe timeline, and the Tokyo timeline.
The OVA/Ryo-ohki timeline is the original timeline released, and is considered the primary canon story. It contains 3 OVAs and 2 OVA specials (which make up 26 episodes of Tenchi Muyo!, the one that aired in America). ...
This is a bit complicated. The links are to MAL, but I've found that different databases index these very differently. Sources are mostly in the links, but I had to reference Wikipedia and Tenchi Muyo Wiki as well.
Tenchi Muyo! Ryo-Ohki is the original OVA series, which was brought to the US simply as Tenchi Muyo (I don't know about other countries). This ...
I suppose this depends on your definition of "often". It also heavily depends on the kind of show you're watching.
If you're watching a slice-of-life anime which has its characters closely rooted in the modern reality as opposed to anything supernatural, then older women are typically drawn closer to what our expectations would be.
If you're watching an ...
The song is titled キミと見た花 キミと見た空 (The flower I saw with you. The sky I saw with you), according to the credit roll of the episode:
According to the official website of Ai Tenchi Muyo, the full version of the song is included in the BD/DVD Volume 1, which is set to released on January 21st, 2015.
愛してるって叫びましょ!! -full ver.-