I don't see how a representative republic with a federal system can be simulated in Civ 5.
A small civ with several allied puppet states is about as close as it gets, I suppose.
The Social Policy "Liberty" offers selections for "Republic" (gaining production) and "Representation" (gaining culture), but that has nothing to do with the geographic expanse of the civ.
It seems, however, that the AI players spawn cities without penalty--but I can't.
um, representation has a direct impact on geographic expanse. I've taken it many times with larger empires. biggest issue for me with it now is that liberty in general is now less desirable than tradition. let's compare the trees:
1.base tradition is +50% food growth in capital. base liberty is +50% settler generation in capitol. food=production when making settlers anyway, so this is at best a small settler production boost for liberty in the early game and a HUGE boost for capitol during the entire game. big win for tradition.
2. aristocracy is +33% wonder generation, collective rule is new cities start with 50% of the food necessary for the 2nd citizen. even bigger win for tradition.
3. legalism is -33% unhappiness from capitol citizens, meritocracy is +.5 happy face per city connected to capitol. legalism is easier to get and has a significant impact throughout the game. the happy benefit for a size 18 capitol is equivalent to 12 connected cities with meritocracy. for small empires legalism is better, for mid-sized empires they are generally comparable, and for large empires meritocracy is better (possibly much better depending upon how many cities you get/map size). however, legalism only has one pre-req which is highly desirable, while meritocracy has 2 (1 meh and 1 poor). about a wash though game strategy is highly important for these 2.
4. oligarchy is +33% combat power in friendly territory, citizenship is workers are 25% faster an building improvements. advantage citizenship in my book, faster workers means less expense or more improvements online quicker. my only beef is that it doesn't stack with the pyramids, THAT would be make citizenship very useful indeed imho.
5. landed elite is 2/3 reduction in culture required for border expansion, representation is +1 culture per city. These 2 have a great synergy. You could literally pick these 2 and not building any more culture buildings for a LONG time if ever. they also both work well with empires of any size. unfortunately, getting both would cost 6 early sp's, extremely unlikely without stonehenge and even then quite iffy. I like landed elite better but this is very close imho.
6. monarchy is +1 gold per 2 citizens in capitol, republic is +1 production/city. I would much prefer republic in any decent-sized empire obviously, but it's two prereqs absolutely suck so it is rarely taken.
looking at the breakdown, that is 2 wins for each with 2 ties. unfortunately, the base policy and lvl 1 policies strongly favor tradition, while the better liberty policies have 1 bad and one bad or one ok qualifiers. generally speaking I would say that even on a huge map I would take the first tradition policy before going for meritocracy, and generally any time I planned to have fewer than 15 cities I would favor tradition as a branch.
