In fact, Safelog provides a function to do exactly that: you create a pseudo-aircraft type which is defined as "summarizes several aircraft".
However, this is certainly not necessary, and there is no reason why you couldn't summarize your totals with one or a few line items. I did this because I had a lot of spare time, and because from now on I've got a pristine digital copy of everything, which is a nice feeling. When I transitioned to Safelog, I decided to spend a few weeks worth of evenings and just enter everything, line by line. This means that you can do whatever works best for you, as long as you (and your future employers) are happy with it.
The FAA doesn't really make a big deal about what method you use to log your flight time, just as long as you log all flight time which you're going to later use to justify currency or a new certificate.
Logbooks are an interesting blend of personal and professional recordkeeping.