Range is significant only in a sandbox environment where the DM consciously makes an effort to use diverse encounter distances and terrain features. You also have to consciously create dungeons with rooms bigger than the typical 30'x40' dungeon room, otherwise pretty much all ranged attacks will be at more or less point blank range. Rarely does range come up in an adventure path, unless the players are the instigators (often as rules lawyers).
One problem I find is common with DMs is that they end up having every encounter be an ambush - usually at close range to ensure maximum carnage. This is I think a legacy of 1e era play where the rules typically had combat over before the first round was finished, so the initiative roll could be considered the 'midgame'. Also I think it comes from a combination of player vs. DM mentality, and not wanting an encounter to be easy, or wanting to impress the players with the monster.
Range becomes a very large consideration in ocean combat, combat with flying creatures, combat on open ground (plains, bandlands, meadows), and siege/standoff situations. It can play a huge roll is skirmish situations, kiting situations, and chase scenes, particularly if you run chase scenes with different movement rules than typical combat.
When reading an RPG rules system, one of the things I look for is its ability to handle certain difficult to handle scenarios well - man vs. cat, hunter vs. deer, and so forth. One extremely difficult to handle scenario that is potentially actually common and relevant to play, is "Party versus sniper" or "party versus distributed skirmishers." A typical scenario might be a group of hobgoblins with longbows is arranged in a wide arc, and have hidden themselves with natural terrain features (trees, rock outcroppings, etc.). There are 30-60 feet between each archer and they diameter of their killing field is 100-200 yards. How does this combat play out in the games rules? Note for example whether running quickly actually makes the targets easier to hit at range rather than harder to hit in this situation. Similarly, another common scenario which comes up a lot is there is an assassin with a crossbow on a rooftop some 50 yards away. The assassin is very skilled at hiding, and it may even be dark. How does this combat play out? The interplay of the games rules on range attacks and spotting things at range is extremely important here. 3e's RAW is actually flat out broken because it assumes an encounter distance of no more than a few score feet.
