When starting a new game allow the user to 'outlaw' or make unavailable certain technology/technological paths (such as the various weapon paths) so that if the user would like, for example, a more 'Star Wars' experience they can just get rid of missiles and the rest leaving only lasers and mesons. I imagine this could also apply to shielding / stealth tech depending on peoples tastes (since I don't think anyone will be wanting to get rid of the production paths etc) but being able to determine the weapon types, and thus the 'meta' of the military in a game could be nice.
This is possible but tricky. The simple implementation would be to flag certain techs as not available. However, those techs affect other parts of the game. For example, removing missiles would require removing techs such as warhead strength or missile agility, but that would leave ordnance factories, ordnance-related logistics installations, the missile design window, ordnance factory options in production, etc. You would also need to remove magazine techs, but they would still be an option in the Create Project window. It isn't as straightforward as ticking techs to exclude. Also, by excluding missiles, you also exclude recon probes, geo-survey probes or sensor buoys, unless you only exclude warheads
In addition, NPRs would have to be able to handle any missing parts of their normal tech, which would not be straightforward at all.
It might be possible at some point to have (for example) a non-missile version as an option for a game, with all the various missile-related elements removed. However, they are an integral part of the game so it would take a while to identify everything that would change. Maybe for a post-launch version.