I think it's great
that you're figuring this stuff out now. We didn't, and it caused a huge rift in my relationship with the ILs...almost four years later, things are still stressed.
Everyone's had really good things to say about what's best...having someone you can count on to cook/clean/etc. while you recover is a BIG, BIG help. For me, it was my mom and then my sister. They took turns living with us for the first two weeks. Just like everyone said--my job was to nurse babies, take a lot of sitz baths (for the bleeding/tear), and sit around a lot. Mom and sis were like little tornadoes of "get it done" activity.
As far as when everyone can visit...people will be a lot less high-pressure if they get a glimpse of the babies right away. If you're planning on being in the hospital at all, the day after the baby is born is a good day for (quick)visitors. Keep the numbers small, because 7 people in a hospital room can get really overwhelming for you and the baby.
Once you get home LIMIT VISITS, and be clear over the phone about your expectations. If your family or your ILs are coming over, say something like "great...for lunch let's just order out." or "on your way, could you pick up lunch?"..that way you won't have to fuss with being a hostess. If you're getting tired or baby is getting frazzled, JUST GO TO YOUR ROOM and lie down. There's no need to sit through a long visit, and if people are overstaying their welcome, a "nap" with baby is a good way to get away.
In my opinion, and it always varies by family, the only people that need to see the baby in that first two weeks are its granparents, aunts and uncles. Your close friends, if you want, too. A huge family gathering complete with cousins, your aunts and uncles, etc. is just too much. Baby will end up getting passed around A LOT, and you'll be stuck with a lot of clean up, etc.
The problems I had were twofold. One, my MIL is very old-school and expected "visits" with the baby to be frequent and uber-polite. She would hold the babies and I would be the one fetching drinks, offering snacks, etc. Never once did she offer to help serve herself (much less do dishes, laundry, or clean up a room). Contrasted with my Mom, who worked first and then held the baby only when I needed a break, my MIL was just awful to spend time with.
The second problem was jealousy between families. My parents were really helpful and really generous--so they were over A LOT (with a new baby, you need help!). My ILs were the opposite
of helpful and never offered food, diapers, etc. That sounds horribly greedy, I know, but it was just the icing on the cake. Visits with them got so tense. Plus, and maybe others have experienced this,...for some reason, I just wanted my MOM around. She was such a comfort to me, and she really pampered me, and I could ask her to do anything. My MIL couldn't understand why I didn't want her in the same way (to me it was obvious), so she got angry with me and has held a grudge for years.
If I had been thinking ahead, I would have made more of an effort to include my MIL more--even if she was a total pain the behind. Then again, it's pretty ridiculous to have to worry about someone else's petty jealousies when your'e 2 weeks postpartum and taking care of twins!
In the end, once we got through the first several weeks, we came up with a rough visit schedule...we'd see each set of grandparents roughly every two weeks. That gave us a lot of "just us" family time in the first several months, and there's nothing more precious than the time you spend together as a new family. Plus then everything was "fair" (double
I could talk about this stuff forever. It was such a surprise to have it be such a contentious issue! Again, good for you for giving it some thought before the babe arrives. Good luck!