- Yes, there are plenty of activities at the resort aimed squarely at kiddos. Plus, there's the pool (which has its own activities), kiddie pool, hot tub, the pool at the beach house, and, of course, the ocean. There are bikes to rent (you can get a tag-a-long if the kids don't ride yet), nature walks around the island, miniature golf, and plenty of yard games right on property: putting green (kids love it), giant checkers, bocce ball, horseshoes, corn hole, and more.
- I wouldn't say DoorDash or Uber Eats are particularly popular, but they are used, yes. In fact, they will deliver to the Beach House, as well. That being said, it's not necessary to use them given the close proximity of so many restaurants, including a few that you can walk to. Others are a very short drive away in Shelter Cove Shopping Centre (you can walk but with kids, I wouldn't), and there are tons more that require less than 10 minutes of driving (or biking). You definitely can eat meals at the resort, but they'll all be quick service. There is no table service restaurant on property.
- Nearby gems. While many like Scott's which is the first restaurant you pass walking from the resort to Shelter Cove marina, during my years working at the resort, I found it to be rather pedestrian. Not bad but not notable, either. Another 6-7 minute walk past Scott's farther down the marina is Ella's on the Water which is better, though slightly pricier. Sitting right beside Scott's is Hilton Head Social Bakery which is a true gem. Plenty of delicious pastries, quiche, sandwiches, breads, desserts, and the like. Definitely pricey but generally worth it. As there is something like 300 restaurants in and around HHI, you will find folks who love nearly all of them. In other words, you can't go wrong. That being said, I'd give Fishcamp on Broad Creek a try--was one of my top three places for seafood on the island and actually takes reservations unlike many others.
- What to know before a first stay? Don't look at this as a typical Disney vacation where you have to plan, plan, plan. This is a retreat where you want to enjoy family, so let the kids run around the resort and enjoy the beauty. Splash in the pool. Sit on your balcony and share a meal from Tide Me Over. Kick back and relax. The low country vibe is what sets apart HHI from all other resorts, that and the best CMs anywhere. So, don't overcrowd your schedule with "things to do." It's not that kind of place, though you can certainly find plenty to do.
Finally, you say "considering renting points this summer." Hmmm, not sure that's going to be possible. DHHIR is a small resort which is extremely well-loved, especially during the summer. In fact, from the early spring breaks through Labor Day is considered the busy season there, in particular, the months from late May through late August. Unless you're very fortunate--and that does happen occasionally--rooms rarely open up. There are only 123 total rooms there, and unless you own at HHI, the chances of someone snagging a reservation during the peak season are remote. Now, watch you prove me wrong!

It's a great resort, so best wishes to you!