I like this one... Even though this for long train rides, at least the downtown to eastern exurbs has been studied. There have been a handful of initiatives to get DART trains into Kaufman County.
Interesting study of possibilities and what ifs by some university student and professor at Texas A&M. Note the link does not include an official TXDOT url.
You can find this study linked at a high speed rail proponent's web sitehttps://www.i-20corridorcouncil.com/capacity-study
along with an Amtrak feasibility study on the same page.
Both studies left out very important stakeholders, the Union Pacific and Kansas City Southern Railroads - you know those who own the tracks and will contract out any upgrades needed to the corridors. Neither railroad participated with either study, so what the studies recommendations might be needed are not what the railroads will require and demand will be needed.
The study headed by A&M did not think Amtrak would need more cars, well guess what the Amtrak study wanted, more cars. The A&M study only looked at capital costs to implement what they thought was needed, completely ignoring operations and maintenance costs. Guess what the Amtrak study concentrated upon, yes you got it right, operations and maintenance costs on going year after year.
While it is fun to read these studies, you have to take them like spilled salt. They are just what ifs.