It's very stupid and detrimental to the development of this game when people flat out reject things from DotA simply because they are from DotA.
This game is based on DotA, and DotA is a very, very successful and popular mod. Get over it. This game's success can probably be measured by how well it approximates DotA's gameplay. Simple as that.
As for item upgrades as opposed to recipes: that works too. We just really need something to add to what we currently have. Just buying a few basic items - chestpiece, helm, gloves, boots, jewelry - with some basic stats on them isn't enough. Not when there are very similar games (game-mods) which have quite a lot of depth in their itemization.
The fact is, one of this game's greatest competitors will be DotA, even though DotA isn't actually a game, per se. If this game has huge, glaring spots where it is weaker or less interesting than DotA, that will hurt its success. Currently, itemization is one such glaring spot.