Most people here on TB will tell you not to worry about fingerboard wear, that it’s just the cost of doing business and that it could take decades before you need to fix it, and that it’s worth it to get your sound even if you have to eventually replace the whole fingerboard, but..
I wore out my Wal’s ebony FB in only 8 years with Rotosound RS66’s under heavy playing (probably bad technique too), it was bad with buzzing notes etc. I had a luthier smooth it down again like new, and I didn’t want to go through all that again, so I started using flats. I went through a few different brands of flats including TIJF’s, but I never was very satisfied with any of them, until I tried the LaBella Black Nylon Tape Wound (750N, .050-.105). I was really surprised how much I like these strings.
Most people say that nickel strings are less abrasive than stainless. The TI Jazz Rounds are nickel and have a thinner wrap which makes them feel much smoother, and are probably going to cause the least amount of wear, and I did use those for awhile.
Ultimately, the choice is yours.
But if you want to preserve the fingerboard, then I would recommend trying the LaBella 750N set, they really surprised me with how good they are.