When choosing a park entrance, I sometimes remember the park operations building that was used in Jurassic World Evolution 1, which is the Security Center Building repurposed as a fixed entrance for parks that do not use the monorail entrance.
I would not mind having a building of this aesthetic that is very industrial and unbranded as an entrance option, one that is accessible from any building set. I want to sometimes make parks that do not focus on guests but on research, dinosaur sanctuary, or one that could work for Biosyn. An alternate entrance that could be utelized in any park may be a nice arrival point option for those wanting to make a more secluded park.