From the beta you really need to bear in mind, gear dropped can REALLY influence your run. Getting weapon & armor drops early can shift the power of some classes massively.
The barb, mobility wise, is probably in the best place in the beta, leap is amazing. His attack speed is pretty slow in the beta if you go 2h, but frenzy makes up for that +75%

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Tbh at 13 most of the classes are in a pretty similar place, the witch doctor being ahead because of soul harvest. I can imagine at points throughout leveling classes will constantly leapfrog each other due to rune and skill unlocks and obviously gear.
I heard that different types of items, starves, swords, bows etc alter the active skills in terms of range, speed etc. I couldn't find any information on this. Do you know if this is on a per item basis, as in you will see how it affects the active skills when you view the item. like it will say +5% range on active skills for this bow or is it all bows increase speed of all active skills by X and all wands increase range of all active skills by X ?
I know that you do get some stats that are increased per item i was wondering if some types of items alter active skills generally, because that is kind of what i got from the dev talk?
Uh this is kind of confusing, so I will just give a brain dump of what I know.
Active skills can be modified by weapons/armor with +skill affixes, these probably wont show up until after normal mode and are on a per skill basis. They will likely be on class specific armor and weapons, and possibly rings and amulets. As far as I know they can modify the resource cost, damage, crit chance, crit damage etc of a skill.
A concrete example would be a fist weapon that makes the monk skill Lashing Tail Kick cost 5 less spirit (down from 30)
Then legendaries and set items will probably have their own unique bonuses which we dont really know anything about yet.