A couple of guys from my group tried RAFA a couple of weeks ago. Converted the British Grenadier Bunker Hill scenario. The RAFA combat system seemed to work OK, though there are a LOT of modifiers. Some of this perception is caused by many of the Combat Contact modifiers applying to both sides – e.g. between two units where the defender is behind fieldworks, there will be both a "+" for the defender and a "-" for the attacker.
Also, just to move a unit can involve a LOT of rolls. Take this sentence from the GC AAR "Feeling the discomfort of the British refusing their right flank the American militia and left flank riflemen attempted to reposition their lines amid the field fence rails to try and flank the British approach only to discover the joys of attempting to manoeuvre militia which only got more complicated as the enemy got closer."
Assume you are going to try to move a Militia that is In Command, in Line, in cover out of its cover, has a friend wavering/routing within 12" and fired the previous Fire Phase:
1. First, you have to take a Fatigue Test (FT) due to being within 12" of a friendly wavering/routing unit. FTs are a D10 roll where you want to roll low. There are 4 modifiers to any FT, and many have additional mods (this FT is not one of them). Failing an FT can have different effects; in this case, failure means your unit takes a Fatigue Hit.
2. Next you roll for the unit for being In Command. This is not an FT, it is a different table, and the one time you want to roll high. A 4+ on a D10 means you can move normally; a 1 means no move. There are no mods to this roll. Also, the In Command and Out of Command tables are not on the published QRS.
3. Next, to move a unit that fired in the previous Fire Phase requires an FT. There are no additional mods to this FT, and failure means you can't move.
4. Next, it requires an FT to leave cover. There are no additional mods to this FT, and failure means you can't move.
5. Finally, if you're able to move, since you're Militia in Line, there is an FT for the first move segment. There are no additional mods to this FT. Fail, and you take a Fatigue Hit. If you can, and do, move a second segment, Militia will take an automatic Fatigue Hit, and must take another FT.
One other point: there is a section in the rules, Fatigue and Morale on pages 56-57, that lists 15 items. 13 of these are different Fatigue Tests that need to be taken. 2 of them are not actually Fatigue Tests; one is the effect of rolling a natural 10 when firing (firing infantry takes a hit, firing artillery is out of ammo), the other is being "driven back" when a unit takes 3 hits from shooting from a single unit. The point is the FT mentioned in #5 above (and five others) is not in that section.
My group is on the fence about playing RAFA any more.