There are a few things that have been left out. This is my understanding as I'm about to make the jump to all grain here soon and have been reading as I'm guessing you have too. Braid vs False bottom. For your sparging if you batch sparge from what I've seen people use braids, if you're fly sparging a false bottom is typically used. That's purely nitpicking as I've seen every combination.
Second is the sparging temperatures. Depending on what you're brewing, type of grains, etc, etc you're initial temperature will vary. I've seen 148 to 155, again depending on the type of grains used (some grains are more refined than others. Take for example oatmeal stouts, if you use instant oats you can throw them right in your mash. But if you buy regular oats you have to cook them before adding them to your mash or else the sugars won't be to a state where you can extract the sugars. Granted that was long winded to get me to the temps. Your first batch will extract the simple sugars (easiest to get to) at the 148 -155 degree temp I mentioned earlier. The reason for the higher temps on the sparging...to break it down simply is to get the sugars that need a higher temp to be extracted. Sure you can by using the same temp but then you get into efficiency and that's a whole other discussion.
Third, as others have said...go big or go home. When I go I'm going to be getting at least a 15 gallon kettle for my boil kettle and then a 20 gallon kettle for my MLT with a 15 gallon HLT kettle. This will let me make big beers for 10 gallons because by the time you do a 5 gallon you might as well do a 10 gallon right? The other thing this would let you do is separate into two carboys and do different combinations, maybe using a different yeasts, dry hopping one and not the other, adding oak or bourbon, you get my point by now.
The only other thing I'd suggest is having sight glass and DEFINITELY a ball valve for ease of emptying in the boil kettle. That'll let you see just how much you've got. As for temp, I'd go cheap and easy and just throw a candy thermometer in. For the MLT if you're batch sparging just a ball valve. If you're fly sparging I'd suggest sight glass that way you can keep the MLT sealed and have a hose from your HLT feeding into your MLT to keep it at the right level. There are several designs around here.