O.k…..need some advice here

After doing a France/Spain 7 day trip & enjoying it….looking at a 2 week trip next year.

I want to get in as many countries as possible without going past 500km/day.

Will probably get the ferry to France and will lose a day each way, so 12 days approx. Anyone done something similar.

France, Belgium, Germany, Austria, Czech, Poland, Italy, Switz etc.

Give us some tips.

Would be staying in B&B/Hotels etc.