I agree that if she is uncomfortable you should avoid it unless that is your only option for exercise. I would advocate keeping her on a flexi lead or long line if you do go. It keeps you in control. If you get an extra long flexi lead you won't get tangled in it and it gives you enough length for a (shorter) game of fetch and other play. I can't stand the things for walking a dog, but as a happy medium for being off leash at the park they are really handy. People walking their poorly behaved dog around on them bugs me and I used to swear I would never use one. Then my mom gave me a couple of her old ones after her dog passed away. Now I think they are great for safely playing with Piper on a quiet street when the snow is 8 ft deep/high everywhere else.
If you keep her fully leashed and ask the other owners to keep their dogs away it usually works well too. I say "can you get your dog please" if they are charging at us because Piper is uncomfortable with impolite dogs.
Alternatively, I've seen vests and leashes that say "in training" on them. People leave you alone more if they think you are training your dog. When you see a dog near by keep her close and see if it helps by giving her a safe place by stepping in front of her and/or leaning over a bit and "sheltering" her by draping your hands over the over her back. (Keep your face up and out of the way though!) Right after Piper's first heat (at 7 months) she must have been giving off hormone signals that seemed to be rankling other dogs - tons of dogs were suddenly very snipey with her. She was young and very confused. Doing these thing helped a lot until the behaviors stopped.
If you are hoping to ease her back to being comfortable - watch her cues. If she is licking her lips, yawning, panting unusually, wilting, hyper vigilant, is showing whale eyes (open wide enough or pointing muzzle one way and giving side eye the other way to see parts of the whites) etc she is stressed and at the very edge of what she can tolerate. Try walking around the edge or just in, and as soon as you see any signs of unease call it a day. Keep it super positive with toys and treats. If she isn't confident enough to play the way she does at home you need to take a step back.
I live in a place of very liberal leash laws. There is nowhere I could take my dog where there aren't off leash dogs. So I get it if this is your issue. People even walk their dogs off leash ON THE ROAD regularly by my house! Ugh. I have taken to working at the empty far edge of parking lots when I don't want to be disturbed by off leash dogs. Parking lots by by busy roads - the hip new place to walk your intact, in heat bitch! Lol
Feel free to PM me if you would like.