Epilating and shaving is better than just epilating alone.
As for how long you’ll stay smooth, that’s decieving. At first, like waxing, you stay hairless pretty long, like two weeks, because all hairs, every single growth cycle, is plucked out. Any hairs that grow back within this period are probably hairs that snapped during the epilator’s attempt to pluck it. Then, the hairs start growing in, and the cycles start coming in as time-staggered waves. Then, you’ll have to epilate about every four days to keep smooth. You’re really better off shaving during these regrowth periods until growth becomes heavier, necessitating another epilation session. And this I say because 1) It’s just so much quicker to shave than epilate, 2) The skin has a chance to lose that ‘lumpy’ look, and 3) Less plucking yields less redness, and less follical damage.
Remember, even though the hair is plucked, the muscle/bulb complex is still alive and well, so even though there is less hair, goosebumps still feel strange because all these little muscles are still tugging on the skin where there was once a hair. One kind of gets used to it and it kind of becomes less noticeable.
Don’t think that one can naturally lose more hair by continuing to epilate. One may lose some, like 3-5%, but hairs that were once smaller, whispier, and sunbleached will come back eventually as straighter, darker, matted hairs, and will counter any small loss made with what seems like more hair. It’s a funny look, and I, personally, did not like how the new hairs grew in at all!
As for plucking at hairs you missed with the epilator: DON’T! Stay away from tweezers, your legs will look far worse if you start going that route. As it is you may start getting ingrowns and may have to work them out, learn not to pluck and pick at those as well.
You are choosing the routine that you feel is best for you, so I should say good luck, but do what you can to keep healthy skin.