One of the keys to great feet is strong feet. My blog is filled with information on strengthening the intrinsics with met doming, the Achilles with 2 positional heel raises, and the arch with single leg balancing and theraband work for the posterior tibial tendon and the peroneus longus. You will find as your feet get stronger there is less need for orthotics and the most stable shoes. I said less need, not no need!
Various types of orthotics give different support. Various types of shoes give different support. Various types of activities need different support. So, this is a lifelong challenge of all of us wanted to stay upright and exercise. What do I need to protect my feet and still participate at a high level? Many use pain as their guide, many have such a high pain threshold that they have to use educated guesses.
Besides strengthening, the tightness you mentioned may play a major role in symptoms. Almost everyone should be on a daily regimen of Achilles, quadriceps, hamstring, iliopsoas, and low back stretches. These should take 5-10 minutes to do before and after your workout, never with pain, and done at least once on your rest days. If you find tightness, stretch 3 times a day until it resolves. If you find you are tight on one side of your body more than another, stretch that tight side 50% more than the looser side.
I hope this gives you my general philosophy. Next time you see the physical therapist ask for a lower extremity tightness and weakness evaluation so you can know the pattern in your body and can work to fix it. Good luck. Rich