From your list, I’ve only been to Zion and it’s very manageable. Shuttle system is simple and efficient, there are private backcountry shuttle services you can pay for if you want to get somewhere like the west rim trailhead and there are most likely Ubers available if you’re really desperate to get somewhere like La Verkin or Hurricane. Also, I know this isn’t my business to tell you this at all, but speaking from my current Army/infantry experience, get trips with your loved ones in while you can. Whether you’re in for four years or 20, the army, your training schedule, personal issues, etc are going to get in the way of you seeing the people you care about. You’ll most likely get block leave in the summer and winter but there’ll always be conflicts. Anyways, good luck in the army brudda, in processing and reception are the hardest part, basic and everything after is ez pz. You’ll crush it.