We recently played a 4 player game and it ended (at 10 points) after 7 hours with very little actual combat. I'd like to find a way to shave a couple of hours off of the game time without reducing the combat and conflict (like just playing to 8 points would do).

My thought was to use a smaller board, removing the 3rd ring of hexes except for the 4 home worlds. This would force players into conlict more quickly and might make the game go faster (due to the smaller empire sizes). But it would also reduce the resources available. This might be offset by reducing empty space hexes, but I'm not familiar enough with the game to see what other effects this might have.

Has anyone more experience tried to fashion a shorter game by using a smaller galaxy set up? If so, how did it work?

If the intention is to shorten the game, then forcing more combat for fewer resources could make the game longer. Combat rarely factors directly into achieving objectives. But if you shrink the map and then find a way to accomplish objectives (or gain victory points) through combat encounters, then maybe it could work.

You could also try king of the hill where Mecatol Rex is the only victory point objective and ending the turn in control of it gives you 2 points.

These are just random, untested suggestions. The only way to really speed the game up is to play with people often enough that they can all execute moves quickly.

The way I try to make the game go faster is by getting more scoring opportunities in play so that players can rack up more points faster. As an upside introducing more objectives makes helps strengthen the value of bureaucracy in the early game. Which leads me to a question:

Were you playing with the orginal strategy cards or the SE expansion varient set?

As far as map resizing goes, I always recommend removing 8 tiles from the map for the four player game (taken from the two edges of the map not containing home systems). This brings the per Empire Galactic wealth to be exactly equal to that of the 6 player game, on which the racial balancing is based.

What I find when we play on the smaller galaxy with more objectives is that the action often starts earlier, and no one every gets their full fleet out (if a player can field all of their ships then there is no benefit to conquest).