Let me take your process apart a bit. You're doing this as a BIAB batch. You don't have to depend on gravity to get the wort out of a mash tun, you have the grain in a bag and can squeeze the bag to get the wort out. Since you are going to squeeze the wort out and have a fine mesh bag to make your filter, you don't need to worry about how sticky the mash is so you can drop the beta glucan rest. It's a wheat beer and clarity isn't expected so you don't need a protein rest either. Now that leaves you with a single infusion at 152. Much easier.
When the mash is over you are going to pull the bag of grains out and start heating the wort toward the boil. That will stop the enzyme action so you don't need a mashout. Squeeze the wort out of the bag of grains and return this to the boil pot. You aren't leaving much liquid in that bag of grains so unless you like to spend money on fuel to boil a bunch of water to steam, you can start with a smaller amount of water too, perhaps 7 gallons or a little less depending on how hard you squeeze that bag of grains to get the wort out. I usually start with a little less water and then pour a little cold water into the bag of grains after I have squeezed it as that little bit more water cools the grains which makes it easier to squeeze and rinses out more sugars.
Do you have your own mill? If so, make sure the grains are milled fine, really fine. Mine look like coarse corn meal with the grain husks all torn to shreds. It's OK, I have a bag to make a filter so I don't have to give up efficiency with the coarser milling necessary for a conventional mash tun. Now with the grains milled so fine the water wets them quickly and leaches the sugars back out quickly so instead of waiting for the 60 minutes for the mash, I only wait 30. Using an iodine test on my wort I find that conversion happens in less than 10.
OG? I always have trouble with that because I don't yet believe the efficiency that I can get with BIAB. I set the software for 80% efficiency and nearly always overshoot my predicted OG. I wouldn't be surprised that if your grains are milled fine so your conversion and extraction are good that your OG doesn't exceed 1.070 with that amount of grains.