I sailed a 22 out of Winters on the Delaware for two seasons. Nice marina. Unfortunately after work sails were a rarity, but they were peaceful. On weekends your best bet is to get out siling early. In the afternoon the powerboats come out on that part of the river and you're dealing with more wakes. That may be an issue for the little guys.
If I remember correctly you have about a 2 1/2 foot draft on your boat so you can get in and out of the Winters/Riverside channel regardless of the tide.
We're on Barnegat Bay now out of Forked River and really like it. There's a lot ot do on the bay. You could shorten your time into Tom's River by taking the 537 exit off of 195 but you'll still be a long way from your place in Avalon.
The Delaware Bay off Cape May can be rough and might not be a good idea for your wife's first sailing season.
Here're links to the NOAA charts online. That will give you an idea of how much sailing room you'll have at each destination.
NOAA Charts Online
Chart 12324, Barnagate Bay
Chart 12316, Little Egg Harbor
Chart 12304, Delaware Bay
Chart 12311, Delaware River, Smyrna to Wilmington
Chart 12312, Delaware River, Wilmington to Philadelphia
Chart 12313, Delaware River, Philadelphia & Camden Waterfront
Chart 12314, Delaware River, Philadelphia to Trenton
One final thought. My wife and I took a beginners course together at a sailing school in Annapolis. It gave her a lot more confidence and eased her mind about seasickness. She loves being on the boat but might not if I'd tried to teach her myself.