Let me start by saying I'm a complete and utter newbie to flight simming, so apologies if I'm missing some key knowledge on any of this stuff.

I was kicking the tires on P2A (I really like it so far), and hit an interesting situation when attempting to fly from KCLE to KORD.
The STAR and approach I chose resulted in a very tight turn in between.
Here's an image of P2A: https://drive.google.com/file/d/1LKXWhAsD3SrFJn_58skIgSTkxSykPBiA/view?usp=sharing

In an effort to get more immersed in the sim, I try to manually enter my flightplans into the plane's FMC instead of importing at the world screen.
What slightly confused me was MSFS 2020 notices the tight turn and actually attempted to round it out.  I was flying an A320, but switching to a smaller plane didn't seem to affect this.
Here's an image of the VFR map mid flight: https://drive.google.com/file/d/1VvIGuNfGuoeGVBZuG0K21EfGIsevL2eB/view?usp=sharing
Here's and image of the in game flight planner: https://drive.google.com/file/d/1ZrvSmDsv9rT7H2iD-Tn6cF7NSwFc_y1P/view?usp=sharing
Exporting the flight plan from P2A into MSFS 2020 results in the tight turn noticed in P2A.

Is this just a case of MSFS 2020 adding extra pathing logic to ensure chuckleheads like me don't create impossible turns like this on accident?
Would a proper flight plan have extra waypoints in between the STAR and approach to ensure turns like this don't happen?
If this rounding out of tight turns is true-to-life, is there an opportunity to add something like this to the P2A planner?
 

When I actually got to the approach, P2A correctly noticed the unrealistic turn and attempted to manually vector me instead.
You can see the approach line in the P2A picture above.  Unfortunately, it ended up giving me rather aggressive turning instructions.
Here's the two relevant lines from the log (I can email the whole thing if desired).

ATC Speak:  Airbus Six Seven Kilo Turn Left Heading Two Four Eight  vectors to the  ILS  approach for Runway One Zero Right at CHICAGO OHARE  INTERNATIONAL   Descend and Maintain Six Thousand feet 13:20:25
...
ATC Speak:  Airbus Six Seven Kilo Turn Right Heading Three Five Eight   Descend and Maintain Five Thousand feet 13:21:00

I set the vector leg distance to 5 NM since I was in an A320, but it seems like it first wanted to put me at the start of the vectored approach, but then quickly decided to have me intercept from my original flightplan instead.
Attempting to intercept the vectors that quickly was simply not doable for me.  The descent from FL100 to FL50 also felt impossible with the intercept approach, but doable had I gone down the full vector.

Are there any possible improvements on the vectoring here, or did I misconfigure something in P2A that caused it to think I was in a way nimbler plane than the A320?

As you discovered, P2A deals with the sharp intercepts to final by giving vectors.  And yes, some flight planners round out the image.

As for getting good vectors, a setting of 5NM for the vector length is probably about right for an airliner.  You could go to 6 or 7 and then bring it back down when you get used to the program's vectoring.  The longer vector legs might help with the descent also, especially those where the vectors take you on a shorter route than the original flight plan upon which the TOD was calculated.

Also, once you start getting vectors, you can press the APPR button to the right of the map and see the intended vector course in Gold which helps you get a better idea of  where you're going.

Dave