I'd heard the same as you, did really great in school, but wanted to only work in L&D or peds, and thought the same way as you about skipping med/surg since I didn't think I'd need it.
I was hired straight out of school to work L&D. This hospital doesn't usually hire new grads in that dept, but because of my grades & other awards I'd gotten while in school, they hired me anyway. I thought this was the place I was meant to be and would be there until I retired. In less than a year, however, I realized it wasn't where I wanted to work and moved out to the Mother/Baby floor as soon as a position became available. Next thing I knew, my kids pediatrician office got me to come work for them at a new office they'd opened up. Again, I thought that was things just falling into place for me. Another bonus was no more nights, weekends, or holidays. Once there (even though I LOVED working there), I felt like I was losing my skills because you don't do as much in an office as you can in a hospital. With that, less pay for the same (or more) hours, and having to commute to another town to go to work everyday, I decided to leave there.
I planned to go straight back to work, but I ended up needing some surgery and then with different things going on with my kids, it turned out that I didn't work for 2 years.
When I did go back to work, I felt like I had forgotten everything I'd learned in nursing school that I'd worked so hard to learn. In L&D, Mother/Baby, or an office, I didn't get the chance to use even half the knowledge I'd gained in school. So, I decided to go the route I'd always been told while in school...start back out in Med/Surg.
Fortunately, I was hired to work on an Orthopedic floor. This type floor usually gets all the med/surg overflow and we get LOTS. I get to see all kinds of things I'd only heard about in school. Luckily, I remembered more than I realized, but still not enough to feel as good about it as I would have if I'd started on a floor like this right after graduating. I'm blessed to work with some great nurses who don't mind answering any questions if it's something I've never seen or can't remember. I wish I had "sacrificed" at least my first year working in some type of med/surg floor just to get a good foundation.
If peds is an area you think you'll enjoy working in, you should gain a lot of different skills working on that type floor. I wouldn't suggest working in an office right off like I did though. ER would be great experience too. But, in my opinion, I wouldn't start out there myself for several reasons.
If I could do it all over again, I would've started out in Med/Surg to reinforce what I'd just learned in school. I think it would've helped me more in whatever other area of nursing I later decided to work in. That's just my opinion. Good luck in whatever you decide to do.