For repelling mosquitoes and flies, it might be worth trying the Wondercide cedar-oil based dog spray to see how it works. I really like the smell of it -- esp. the lemongrass one. Before you invest in a big bottle, you might order one of their $10 sampler packs of different scents. The downside of it is it doesn't last, so you have to reapply every time the dog goes out. It's effective, but probably not 100% -- it likely will keep you and her both more comfortable though.
My dad has had great luck with Bayer's Seresto collar. He's in his 90s and too old to fool with topicals, so the collar is very convenient because it's so long lasting.
For RX meds, I like NexGard very much for flea and tick control. Whenever the rescue pulls a tick-covered dog out of a shelter, our vet doses the dog with a NexGard because it's so effective on ticks. It's chew that they eat for monthly protection -- pricey, but it works. Bravecto is a better deal because you get three months of protection out of each one.
Rabies boosters for seniors is SUCH a hard call. My vet and I went back and forth on this with my last oldster in his later years, and he was supportive of either decision -- warning me of the local consequences for not doing it, but sympathetic to feeling like enough is enough at that age. It probably depends on the dog -- does it interact with people regularly? It's not really the bites that scare me, as my dogs don't bite people, but the turning the head quickly with an open mouth and accidentally dragging a tooth over an arm they didn't know was there, or accidentally scratching someone when batting them with a paw asking for a head rub or ball throw. The stupid accidental stuff counts too, unfortunately.