If you stop and take the ME private after 15 or so hours, then the next 50 or so WILL be PIC. That's the way my flight school did it. It's a pain, but it's what, $300 with a DE for the checkride? I did ME first because I didn't want to struggle for multi time. I had too many friends with 800-900 hours and only 25 multi and couldn't get an interview. Also, if you only do a ME add-on, you'll have 15-20 hours and no PIC. You're not going to get hired with 15-20 multi, so you'll have to get an MEI and instruct, right? Well you need 15 ME PIC to get an MEI, so that's 15 more hours out of pocket. Plan on needing 100 ME with the current market. Just something to think about.