On how projects "scale", there are certainly python projects with hundreds of thousands of lines. Go try modifying those and see if it meets your expectations.
On your development speed, I can't speak as to how well your setup works for you, but I think you might be missing something. For example, PyCharm does have find/replace. Google if you don't know how to find it. I doubt the two seconds you would spend bringing up the dialog takes much time. Also, the language you're using and your skill level with it affects development speed far more than the IDE ever will.
On how projects "scale", there are certainly python projects with hundreds of thousands of lines. Go try modifying those and see if it meets your expectations.
On your development speed, I can't speak as to how well your setup works for you, but I think you might be missing something. For example, PyCharm does have find/replace. Google if you don't know how to find it. I doubt the two seconds you would spend bringing up the dialog takes much time. Also, the language you're using and your skill level with it affects development speed far more than the IDE ever will.