Are there other examples of human-electric hybrid aircraft?
Yes. I assume by hybrid you mean that propulsion is provided by a solar-powered electric motor while the control system is powered by a human pilot.

From Paul McCready came Solar Challenger in 1981, certainly less flimsy than the Gossamer Penguin.



Solar Challenger (picture source)

In the same year, Solair I flew for the first time, followed by Solair II in 1998. Both were built by Günther Rochelt, who also built human powered aircraft.



Solair II (picture source)

Rochelt's Musculair 2, the fastest human powered aircraft until today, inspired Eric Raymond to build Sunseeker in 1990. Sunseeker II improved on those designs again, still using the layout pioneered by Musculair 2. It flew first in 2002.



Sunseeker (picture source)

Icaré 2 was based on glider technology and flew first in 1996.



Icaré 2 (picture by Uli Reinhardt, Zeitenspiegel (Zeitenspiegel) [CC BY-SA 2.0 de, GFDL or CC-BY-SA-3.0], via Wikimedia Commons

With Sunseeker Duo the first solar-powered two seater flew in 2014.

For a comprehensive history of solar flight see here (PDF), and for some more background see here.