There haven't been duels to first blood for years. Specifically because folks created a guild for dueling to first blood. Dueling isn't for sport, but for honour. There *are* duels to surrender and death. And there *are* training matches.
Many of the suggestions for duels already exist. There is a huge amount of random chance in duels. If your skill is even somewhat near another, it should make a difference, say 20% difference or so (I'm estimating after not having looked at that code in years). So unless you've got 15% vs 75% skill characters in a duel, there's a chance the less skilled character defeats the more skilled character. Again, its been quite some time since I looked at the code, but I vaguely recall there's a few 'rounds' behind-scene.
You do gain swordfighting, leadership, and jousting skill in battle, dependent upon your unit type. Perhaps it needs tweaked. That seems a reasonable suggestion if someone wishes to champion a change. Skills decrease with age, starting at age 35, I think. I think the decrease increases with your age, but again, haven't looked at that code in quite awhile.
There was a five year period where swordfighting gains were not increasing due to battles, but that was fixed two years ago now.
This topic should probably be split.