I'll just give one warning about editing: unless you write a GUI interface for every type of data you have [1], it's pretty tough to actually edit single entries. It gets really tedious to type out "UPDATE sometable SET somecol = 'something' WHERE uniquelyidentifyingcondition" every time you find a typo.

You probably want a GUI for adding entries, too. But the initial inserts can be done with a bulk loader written in Perl. The bulk loading is the easiest part.

[1]: web frameworks with a 'scaffolding' feature help immensely here.