What about:

- fly into Germany, say Stuttgart (low cost hub).
- do your heritage bit in Germany for a day or so, using the excellent train system
- cross the border into NL and do the empeg meet, again using trains (http://www.ns.nl). The meet is 500m from Amersfoort Schothorst station.
- take a cheap EasyJet flight from Amsterdam to Luton, UK
- hire a car and go over to Cambridge
- drive down to London, drop off the hire car
- spend a day or so doing the sights (although that's not a lot of time)
- catch a connecting flight from Gatwick to Stuttgart
- catch a return flight home.