Choose plants that grow a similar size and shape. I hate having to do wonky canopy management because every plant ends up a different size.
That’s just a personal preference though I suppose.
I would even encourage you to do 4 of the same, or maybe just 3. You didn’t mention how big your space is. I grow in a 3 x 3 tent and now I always do 3 to make sure there is enough room for them after the stretch. I used to do 4, but after running out of room a couple times I just do 3 now and my grams/watt hardly went down, each plant just produces a bit more. Especially with autos you don’t want to have to prune them just to make space, only when necessary to help with light penetration.
Also consider some plants have different nutrient demands and adding that as a variable could increase your learning curve, and some plants are just harder to grow than others. On your list: Super Silver Haze, AK47, Sour Diesel are all good starter strains, but the SSH is likely to get taller than the other two due to its sativa heritage.
The last factor you should consider is the breeder, and if these are all stable auto crosses. Many of the larger breeders that mostly crank out “auto” versions of long established photo strains don’t take the time to do enough back crossing to get stable auto genetics. This is pollen chucking, not actual breeding. ILGM and Fastbudz both take this approach, great beans can come from both of these companies, but they can also be inconsistent. Since they don’t actually breed any original strains I would almost consider them more seed producers than breeders. A proper breeder should have some information about their process, look for stains that are at least 3rd generation for the best chance of a stable cross with reliable auto flower traits. An exception is if plants crossed from two stains that were 3rd generation or more, then their offspring should produce a stable auto in the first generation.
Check out:
Mephisto (my favorite
Brother Mendal
Mandolorian
Dinafem
Most of these breeder specialize in autos and they are all fantastic.
This is probably not really the information you were looking for, but I hope some of it is useful nonetheless. The best genetics will help set you up for success.
good luck!
