Hero Stat Balancing and Damage

Ok, I have a AOS/DotA type map in progress, it's going great (besides trying to having to get used to were everything is on the Unit Editor) but i've come to a point were I need to balance my heroes so they will be equal (To some extent). I usually just go all whole numbers, and usually use atleast three numbers for starting points (Like 15, 20, and 25 and then mix those around for Str, Agi, and Int and also do almost the same with the amount raised per level except lower numbers) but that usually leads to very strong heroes and I don't want them to be monsters. Anyone have an Idea or a way I can balance the heroes stats and damage without making each too powerful one way or another? Thank You for your help!

Not all stats are created equil. Str gives health and heal rate. Int give mana and recgarge rate. Dex gives armor and attack speed.

Since some of those are better in hero vs hero than others you will have a problem if you just cycle a fixed set of numbers around. You can counter balance some of the secondary benifits of each stat.

For example you could give a dex based hero less of a armor bonis and a str hero less of a health bonis. Or you could give int based heroes bonis in armor and health.

How you can balance depends a lot on weather or not players can make heavy use of tomes. If they can it will be much harder to balance. Also the abilities of each hero will greatly effect thier balance.

Tomes are ok in moderation but if they can be used too much it becomes a game of "Just grab a dex based hero and tome away".