If you’re going indica dominant and have the space, you could go and utilize bigger than 4x4, unless you got a 10’+ ceiling, then let us know because you can go real big with a plant.
Or, listening to your time constraints, if you ie: have a good 3x6 spot inside, I HIGHLY recommend getting two tents (two 3x3s or two 4x4s or w/e will fit and looks like a good buy). One to veg and one to flower, dial down and set each tents lighting and environment perfect and never touch it. Your “flips” will be as easy as taking a plant from tent A and to tent B, and making sure no settings change.
One tent now for a month or two is fine, but plan on a veg/nursery tent AND a flower tent. You can keep it to 4 plants, have two getting huge and healthy in veg, and then have two cruising in the flower tent, stagger their age how you want, but I think this should/could give you much greater yields than 4 plants in one tent.
I’m thinking 2-tents will double your production, but it could probably be pushed on a tight time schedule to almost 2.5-3x your “production-per-season”. Also this plan let’s you build the first tent and learn from it for building the second. And if one tent/part bites the dust, you have a second settup handy.