In terms of speed, we'd say the sweet spot to aim for is around the 3000MHz mark for DDR4. For DDR5, We'd say to aim for 4800MHz and above, although at that point it really depends on your coffers ...
The MSI MAG Z790 Tomahawk Wi-Fi is the best Z790 gaming motherboard you can buy right now, thanks to its wealth of features, support for any Intel CPU, and reasonable price tag. At $319/£337/AU ...