Hey Iceman......
You have done your homework with regards to shore dive and I will only comment on certain parts of your trip that I have dived.....
First off: Be aware that rental cars with families wandering down to some beaches are obvious targets to thieves. As a rule of thumb...... leave NOTHING in the car and for an extra measure of safety, just leave it unlocked. If your ID and key can fit in a waterproof box that can go with you that's awesome. Only bummer is if the key has a chip in it and the box gets swamped. I would almost advocate you leave someone on shore with the towels and keys and such while the rest of you snorkel or dive......
Secondly..... Some of the reef structure that is snorkel friendly can be a good distance off shore. Take Makaha for example. Good beach to lounge on with a lifeguard station (so yes, bring your dive float) but a fairly sizeable swim out to where the reef gets good. 15 minutes is sticking in my head for some reason. There used to be a shallow buoy at about 10 feet that could serve as a reference point. The swim is obviously going to be longer and more taxing if the surf is up. Which brings up my next point.
CHECK THE SURF REPORT!
Surf News Network If it's anymore than 1-2 I would evaluate the conditions for a good few minutes before heading out. There are certain dive sites on your list that I think may even be closed out in the summertime if there is any sort of South Swell. Those include Magic Island and Blow Hole. Magic Island is especially problematic if you try to access it by swimming through the rockpiles at the end of the lagoon. Certainly an easier route is to go around the lagoon on the Diamond Head side but this puts you very close to boat traffic coming in and out of Ala Wai Harbor. If you have never dived Blow Hole before I wouldn't suggest it even in optimal conditions unless you have an experienced guide.....
Finally..... You are coming in July and that is a very good thing with regards to shore dives on the North Shore. I can't think of a summer in the past where the conditions to dive up there haven't been epic and very mint come July. Parking can however be tricky. If you are going to get there early then it may make more sense to do 1 day at 3 tables (2 tanks) and 1 day at Shark's Cove (2 tanks) with a third day at the Trench (3 tanks). All of those sites have their goods and bads.
Good: Cove has a shower and relatively easy entrance (boulders and rocks)
Bad: Can be a confusing maze of tubes and swim throughs if you have never dived there...... A good DM is key.
Good: 3 Tables has a WAY better beach for lounging and easier access with soft sand to start for snorkeling
Bad: If current is ripping you might end up around the corner in Waimea Bay and not even notice...... also, no shower facility and restrooms are a 5 min walk
Good: Haleiwa Trench has easier parking and a shower and restrooms close.... Tons of turtles!
Bad: Longer walk to the waters edge then trudging across lots of spiny sea urchins before reaching the drop off. Tough to snorkel with barefoot fins (OUCH!) and even tougher at low tide.
Also..... Makaha is not the same as Makua. Pray for Sex is WAY out there and I don't even think the Honolulu Police Department shows up if you are the victim of a smash and grab so be careful
I'm trying not to be too much of a Debbie Downer but rather injecting some caution into your plan. Finally, it will depend on where you rent tanks but you could spend an awful lot of time driving to and from each side of the island.
If you are a fairly experienced shore diver and you dive quite a bit I might suggest the following tweak to your schedule.....
Day 1: Shark's Cove x 2 (left then right)
Day 2: Three Tables x 2 (left then right)
Day 3: Haleiwa Trench x 2 (right then left or across to the far wall)
Day 4: Kahe Point x 2
Day 5: Makaha Beach/Caverns x 2
In closing I might also add that you will do best to stay to the North and West shores if there is any kind of South swell. If you have questions regarding specific sites or would like to set up some boat dives please let me know. We also guide daily dives on the North Shore in the summer time!
All the best and I hope other SB members find this post helpful....
G