yes but dragon arow doesnt just make them sniper but also ignore enemys defence, i am ok on units lvl 1-2 it might be not needed since boost is not high but for heroes and high lvl uniits it a must be

Well there are other good first spell than dragon arrows. But well I see why with Skeleton Archer it's more interesting. For long range Mass precision could be better if you have 3 long range stack that are higher level. Myself I don't use enough those spells for long range units.

Well by the end of my game I was running:

1 Hunter stack ( sniper )
1 Elven stack ( sniper )
1 Skelly Archer stack ( No sniper )

I'd also managed to get a lot of crazy archer bonus items so I could one shot most enemies. If the enemies were melee I could wait with my skeleton archers, then fire once the enemy had moved closer, after casting mass precision of course :). If they had multiple ranged stacks, I'd usually end up using dragon arrows to make sure my skelly archers could lend their firepower without penalties.

I'm really looking forward to playing my Mage. Mass precision and Dragon arrows in the first round, or Mass precision and Demon/Dragon Slayer spell in the first round later in the game :) I was suprised there was no undead slayer spell though.