The only way a rototiller will have a chance of working is with a min-till approach. I hold the rototiller so high with the 3-pt hitch that the tines barely touch the top inch of soil. Just enough to scratch the surface. Deep tillage disturbs the natural soil tilth and introduces oxygen into the soil burning the organic matter at an accelerated rate. This significantly reduces nutrient cycling. High quality fertile soils can withstand the abuse of deep tillage much better than marginal soils. I find no-till and min-till methods are the best for soil health in the long run. I've improved my soil health enough that I have not needed fertilizer in 5 years now.
Take some time and read through Crimson N Camo's Throw and Mow thread. He takes the soil health principles espoused by "Ray the soil guy" from NRCS and applies them to small equipment food plotting. You can google "Ray the soil guy" and watch some of his videos. They are aimed at large equipment commercial farmers but he explains the principles well. Watch his short infiltration video first. It is an eye-opener.
I've seen cultivators used successfully for min-till. When you select smart soil-building crop mixes, you will build OM over time improving your soil. When I'm done min-tilling a field, it still looks green, not brown. Some have called it "Thirt" (Thatch/dirt). It is mostly chopped up vegetation with a little soil mixed in.
If you try traditional tillage with a tiller, you will find you will be replacing tines quite often; both labor intensive and expensive. While no-till methods like T&M work best, sometimes soils need to have the surface scratch up until they have time for organic matter (OM) to build. OM building is a slow process that take years. I've seen cultivators and light discs with a single pass work to scratch the surface. Discs should be set close to straight with a slight non-aggressive gang angle.
If, for whatever reason, you decided to do tillage, a disc will hold up much better than a tiller when rocks are involved.
Thanks,
Jack