Well, here go my thoughts on this. This is definitely an interesting plan that I happen to oppose.
First of all, I am always very weary of any reform for the federal government that deviates too heavily from the RL United States model of government. At the end of the day, 95%+ of players are Americans and therefore keeping it relatable to them is a decent worry to me.
Secondly, there is already a region that has a semi-presidential system of government, that being Lincoln; which introduced it in early 2019 with the Philladelphia Plan. And it hasn't been the greatest experiment. I've actually been one of its strongest proponents but even I have to recognize it has several shortcomings, like having a much less powerful governor, having power be too divided between too many people ending up unable to do anything, some arcane procedures, etc.
The regions are the place to experiment with alternate systems of government; and sadly Lincoln's experiment in semi-presidentialism has been a relative failure.
I do not want for the federal government what Lincoln has; and I say this as one of the people who supported the system and as the still sitting senator for the region.
In fact, this seems to even bring back the government vs opposition dynamics of Lincoln and modeled after said regional plan.
The only point of that reform I would agree with is the switch back to unicameralism, which would make legislative activity easier. I described a lot of possible ways for Atlasia to go back to unicameralism
in this thread; but none of the options are ideal.