Unless Warcraft changed something, mundane crafting does not cost XP
Mundane crafting requires Craft skill checks, but no Item Creation feats, and the costs are only time and money, not XP. Specifically, they cost a mere ⅓ of the base price of the item, but crafting takes a number of weeks equal to
(P×10)/(DC×check)
where P is the item's usual price in gold pieces, DC is the Craft DC, and check is the crafter's Craft check result. This formula results in phenomenally long times, but at ⅓ the cost there is a lot of savings.
Magic items require XP, but that is easily replaced
In many places, XP costs are replaced with gp costs or vice versa at a 1:5 ratio. Since magic items cost 50% the base cost in raw materials and 4% the base cost in XP, you can apply the same conversion: five times the 4% is 20%, which can be added on to the existing raw material cost to get 70%.
Thus if magic items simply cost 70% of the base price to craft, instead of 50%, but don't require XP, this is consistent with the original system. Taking an Item Creation feat only enables a 30% discount but doesn't leave you behind.
I have played in quite a few games that make this change; it didn't dramatically improve the popularity of Item Creation feats for players, but it does make them much less of a headache for the DM.
If playing with Eberron Campaign Setting (the book, regardless of whether you play in Eberron) in play, the artificer and Artisan feats do require a little more tracking: it is important to remember that 50% of the base price is the original raw material gp cost, while 20% is the "XP" cost. The artificer's Craft Reserve and Retain Essence class features, as well as the Artisan feats, should be applied before adding these together as the 70%. The Craft Reserve should also be multiplied by 5 gp/XP for consistency.
If either is too expensive, these items were not intended for characters of their level
These processes both result in significant discounts. The value of items is used to control the power of items that players have at a particular level, which is part of the system used to try to ensure that enemies the same level as the players are challenging without being impossible. Making items cheaper or giving players more gold may allow them to steamroll opponents; making items more expensive or giving players less gold, or giving them gold but no place to spend it, may leave players without the tools they need to contribute.
In my experience, there are many classes that just barely find the default wealth rules sufficient for their needs – if they spend carefully. Other, more powerful classes are not nearly so needy, and could do with less. As a result, reducing wealth is something I strongly recommend against – it disproportionately hurts the classes that were already weakest.
On the other hand, I tend to find the system has a fair amount of room for extra wealth before players really start to steamroll. Thus, your choice to make it easier to get items is a move in the better direction.
But do be careful; wealth expectations are a rather fundamental design assumption of the game. Great care should be taken when modifying it. I tend to recommend that new DMs stock fairly close to the guidelines. It takes experienced DMsa lot of care to get modifications to wealth to work the way they want.
