Hi Rudi,
Well, the weird silence from me was due to no good ideas or
suggestions. If you have a copy of Knuth's "The Art of Computer
Programming" available, then he has placed a difficulty level on
the exercises in his books.
00 Immediate
10 Simple (one minute)
20 Medium (quarter hour)
30 Moderately Hard
40 Term project
50 Research problem
I think he underestimates some of the difficulties on some
of his problems. Anyway, you might find one of his exercises
could give you an idea for your degree problem.
I just have a B.A. in Chemistry, so did not get as far as you
seem to have gotten. And I am not too good at coming up
with new ideas. At least the good kind.
Regards,
Steve N.