Its your first post here at CFC, so welcome.
If you want quicker war and possibly simplified games, then you might want the Scenarios.
You cannot, without resorting to work and testing and balance as a scenario, alter the availability of city improvements, or re-tie the tech tree's advance dependencies. It can certainly be done, but of these changes have effects on the AI, and then have to be tested a bit to make sure you get the effect you really wanted from the AI.
But if you were playing 15 years ago, then might not have the huge number of scenarios with the Gold Edition, e.g. Scenarios are at least designed and tested by some people, and some are very fun and give Civ a totally different feel. Some basically make research almost irrelevant, and you must concentrate on military, disposition of forces, even diplomacy. Many modify the tech tree, improvements, units, and even forms of government (including "new" governments like Facism).
Do you have the base 25 scenarios like "ALEXANDR" (12/4/1996)(804 files, 67 folders, 53 MB; can compress to 22.6 MB), and do you have the extended 90 scenarios like "1861USA" (464 files, 93 folders, 22MB/4.5 MB compressed)? I think they already available for download, but if links are broken, then it might be possible to make uploads of them, as I have all the originals. There are also many more recent scenarios, developed and posted here by CFC members. The scenario league would also be the most authoritative regarding specific ways of modifying Civ 2 like you are asking about.