that leaves it wide open... is there a style you like? I think you should start there. you can google homes by style and sq ft to get you started. If you prefer 1 story, I'd probably look under ranch styles. You'll be overwhelmed with the options!

A lot of ranch styles have the 3 bdrms on 1 side w/a bdrm across from the mstr - that'd give you one for a baby just across the hall. Keep both doors open at night until you feel you don't need to listen for every sound. Or even use a baby monitor when they get a bit older.

you'd have a hall bath and a mstr bath.
you can get a lot of what you're asking for in that sq footage.

Yes, I've looked at thousands of plans over the past couple of months....but I've not been able to find one that is symmetric left to right, with the bedrooms all grouped together, and a decent kitchen. And I would like more than just small coat closets in the 2nd and 3rd bedrooms.

http://www.dreamhomesource.com/house-plans/dhs/dhsw72938.html?from=search

You don't need to add the garage in this one.
http://www.dreamhomesource.com/house-plans/dhs/dhsw47015.html?from=search

This plan is much larger than what you need, but it is a simple plan that you could use as a foundation for your own personalized plan. Shorten it to remove a bedroom, and reconfigure it a bit to have one BR open into the master. Perhaps two masters, one on each end, with one a bit smaller than the other.

Here is a link that might be useful: modern symmetrical plan

If you don't mind my asking, why do you want it to be symmetrical? Do you want to include a front porch or just flush across the front? Do you care how the back of the house looks...or is asymmetrical okay?

If you don't need a garage, you might try cottage plans and vacation homes. Often they don't have a garage and the cottages, especially are often quite charming.