Weapon skills progress towards their next increase by a fixed amount per successful hit on a live target, not by variable amount of damage done per hit. The best strategy for faster weapon skill increases is to use the weakest possible weapons to do the least damage per hit, keeping the enemy alive as long as possible so you can "score" more hits on them.
Marksman: Use an Iron or Rusty Iron Bow with Iron Arrows (at most 16 damage per hit at 100% condition). Carry plenty of arrows so you can turn enemies into "Porcupines". Good tactics for maintaining your Health are to 1. keep your distance by running backwards while aiming, and 2. aim through the holes in closed/locked Ayleid Ruin gates (enemies can't open them, so you're perfectly safe).
Blade: Use a Rusty Iron Dagger (at most 3 damage per hit at 100% condition).
Blunt: Use a Rusty Iron War Axe (at most 5 damage per hit at 100% condition).
In ALL cases, don't Sneak (no damage multiplier) and don't use power-hits (no damage bonus). Remember, the less damage you do, the longer the enemy stays alive so you can keep hitting them!
You can extend the battle duration (potentially endlessly) by healing the enemy. Create the longest duration Restore Health on Touch/Target spell you can. Cast it once on them to start their Health regenerating, hit them over and over while it's in effect, then repeat. If their rate of Health regeneration exceeds the rate you're inflicting Health damage, they're effectively invulnerable so the battle can last as long as you want it to!
The lower a weapon's condition, the less damage it does per hit. Create a Disintegrate Weapon on Self spell and cast it repeatedly to deliberately reduce the condition of your OWN weapon. You're walking a fine line here, because reducing its condition too much means it breaks sooner in mid-Combat, forcing you to switch weapons. When using Repair Hammers, deliberately don't repair weapons all the way to 100% (or 125% if you have that Armorer perk) to keep their condition low so they do less damage.
The longer the enemy fights, the worse their weapon condition becomes. Eventually, it will break and they'll switch to the next best weapon in their inventory. If they have none, they'll pick up the best weapon off the ground if any are lying nearby. Failing that, they'll resort to Hand-to-Hand combat or flee. It's worth picking up weapons mid-battle (even if you take hits doing so), to keep them out of enemy hands. That way, they'll have NO option but to resort to Hand-to-Hand.
Casting Damage/Drain Strength, Damage/Drain Fatigue and Disintegrate Weapon spells on the enemy will weaken their attacks so they do LESS Health damage to you. If you Damage/Drain their Fatigue to zero, they'll fall unconscious and you can hit them repeatedly while they're down and unable to hit back!
Hope this helps.
