I personally am not too big a fan of low lift flow on street used engines as i do not like the fact that low lift flow usually makes engines more prone to being pipey (being more dependent on correct exhaust length, etc, etc).
For my part, i usually try to on various, similar time period, heads that i work on, to raise the intake floor and lay back the SSR in order to shift Eddy flow/turbulent vortices on the SSR up to higher gas velocities/rpm range, while at the same time keeping in consideration the fact that the fuel mist/droplets follow/s a different flow path then the lighter air.
This (personal taste) approach is based on maximizing flow and coeff of flow in the mid to 80% valve lift range and use, if available, cams with steep ramps and moderate overlap lift(overlap area) while keeping the gas velocity high in less critical areas of the intake port.
For that reason I ordered myself a while back the 250-40 cam for my personal engine build in order to also gain on the valve lift offered by that profile coupled with early intake closing in order to achieve a nicely tractable engine.
The overlap flow area will get quite increased anyways with bigger valves hence in my experience better to stay with somewhat moderate overlap duration.
Furthermore I made in a lot(actually most ports i work on ) of cases good experience with intake floors that are at the SSR apex as wide as possible, hence classic d-port shape
One has to watch out in my experience in order not to overdo it and create dead areas in one of the most sensitive areas of the intake port and also to not create an intake port that somewhat behaves like a straight bottom 2stroke piston port intake (thus instantaneous pressure release making imho the engine once again pipey).
So given the above mentioned facts i usually spend the most time on new port shapes (according to used cam profile) with a venturi/prandtl tube probing the ports in order to find (based on experience and software simulations) out what suits the port/cam combo the best.
The exhaust port on the Xs as is, is already pretty huge so I plan to level it a little out with slightly larger exhaust valves and trying to find out a more homogenous port shape, but being honest, given the pressure difference between intake and exhaust and the importance of the intake port i usually spend the most time on the intake port.
One will see (as mentioned did not have fully time yet to investigate) how much room is in the exhaust port to operate with the Tig torch as i would be tempted to raise the port floor there by welding in order to get a nice d-port there as well, but as mentioned that will be definitely of non priority as for such a build there are other things that are of far higher priority (eg valve reangleing given the cam profile and planned valve sizes).
I'm for my part will stay with the 360°twin crank lay out as i like the engine characteristics besides being already the happy owner of two 90°twins, and vibrations do not really scare me as i do not plan to ride to Patagonia or cape north on that bike anyways hahaha.
Hope that explained in brief a hint my philosophy.
Happy new year and kind greetings to all of you!
Christian
Ps:
@Oldnwiser
No reason to apologize for anything, in particular not for technical discussions, don't worry