Hi Stanley, that's a legitimate question but not so easy to answer. Each crank model has a slightly different lateral position of the ring, and the gap also depends on the size of the ring (the bigger the ring, the smaller the gap). So there is not one frame shape that can prevent the gap from being perfect for chain suck in at least one crank/ring configuration. Therefore the first step is to have your drivetrain set up correctly and maintain it well, that solves a lot of issues. And the second point is the right drivetrain for the right purpose. You can see tons of issues for example with people riding gravel using Ultegra or DuraAce groups, where the rear derailleur doesn't have a clutch or damper. Those groups are simply not made for that use, that's why Shimano has GRX. Same with the Campagnolo road groups. For SRAM it doesn't matter as all their groups have dampers in the RD to avoid derailment. Hope this helps a bit.