I am
not an expert in the radio field so take my recommendations with a LARGE grain of salt. I think before you go off to search about creating a radio system yourself, you're going to need to consider a few options. I see that the farthest away that you could possibly be on a "village wide" application is around 3 and a quarter miles.
1 ) Keep the talkabouts and shift your channel usage. Assuming that you have a 22-channel (FRS/GMRS combination) radio, you should consider using channels 15-22. Channels 1-14 (especially 8-14) are limited in their transmitting power due to FCC restrictions. This may give you the additional range you are searching for. If you only have a 14-channel talkabout, you are probably using an underpowered FRS radio and should read the following paragraph.
Consider more powerful GMRS radios. I don't know the specifics, but there are radios out there that can operate at higher power (I think).
Technically, you (and everyone else using the radio) should have an $80 license (each), but there are people out there who use it without the license.
I also found this video on the forums, this might help you a bit.
How-To Optimize the Range of your Talkabout Radio - YouTube
2) Consider MURS if you are planning largely for outdoor use. From what I can tell, they tend to work better outdoors. I believe you can use MURS
legally without an FCC license.
3) Ask your Explorer Adviser whether or not you can use the current system your Police Department already has in place. I recently moved, but in the area I lived in, their post were issued Motorola XTS2500 radios whenever they were doing events sanctioned by the Department. The rules were highly restrictive on its use and kept to emergencies only.
4) Old fashioned citizen's band (CB) radio, no license needed, has pretty good range, but I believe there's a lot of trash on it now which could cover up some communications. There's mobiles, bases, and portables for this option.
Here's farther information on GMRS and MURS:
General Mobile Radio Service - The RadioReference Wiki
Multi-Use Radio Service - The RadioReference Wiki
I think overall either MURS or GMRS will work just fine, but you would definitely need feedback from others. I think you can buy base stations for both, but I don't think you can buy a mobile for either. If the range is not to your liking, then you could consider making a GMRS repeater, but I have no idea how one goes about that process. If you really want mobile, base, and portable operations and seriously want the range, you could go through the complicated process of FCC approval and building a brand new radio system that would cost quite a bit.