On Sat, 18 Sep 1999, Phuc Tram wrote:

Ifurita and Makoto (El Hazard)
Belldandy and Keiichi (Ah! My Goddess!)
Deedlit and Parn (Record of Lodoss War)

The problem is not so much the ages, it's that Shinji is nowhere near mature
emotionally and a lot less mature than most teenage anime characters like
Makoto and Tenchi; and that Misato is a parent-figure to Shinji, who Shinji
already depends on.

(By the way, Belldandy/Keiichi is not different ages at all, at least not in
the OAV series, since Belldandy and Keiichi were kids at the same time.)