I like the SBG, but I think that the opposed dg combat roll is a little bit too random. Difference in fight values only matter when you roll a tie, so an F7 character does not have a better chance of beating an F2 Goblin, than an F3 average warrior...
Since SBG is one of my favourite games, I hope you don't mind me pointing out why I don't have a problem with this.
You're right - when two normal warriors face off, the one with the higher Fight values has a 60% (-ish) chance of winning, the one with the lower value has a 40% chance. That allows your weedy but undaunted hobbit to roll to wound an hideous, brawny uruk about 2/5 of the time. Or learn to start ganging up on him. Conversely, to hold off the faceless hordes, an elf just needs to keep rolling those sixes...
In fact, I kind of like the simplicity of the basic mechanic. That's just between mooks though - the SBG is a game of heroes. Heroes have a higher strength, extra attack dice, Might points to modify the roll, and special abilities. I could be wrong, but I don't think there's a single F7 fighter in the game who has no other bonuses, and most F6 fighters are heroic characters too. Most decent "combat" heroes are veritable killing machines against ordinary troops.
I do think that combat is weighted towards numbers perhaps a little too much, but the balance between spending points on high-quality heroes or hordes of troops is one of the core tactical choices in the game. Another important tactic is the use of "combat multipliers" - ganging up, banners, spears and pikes - to shift the odds in your favour more regularly.