I know that GregTech has a feature that automatically unifies ingots on the fly, but I kind of wish something like that existed outside of GregTech.
A while back I whipped up a mod to do just that:
OreDupeFix. Unfortunately, I stopped developing it since I started using GregTech instead (sorry), so it is only available for 1.5 and 1.4. I released it as open source, if anyone wants to take over development and keep it updated. Should not be too difficult for someone to update, I just don't have a personal need for it anymore now that GregTech has built-in automatic unification. And GT's is better, in the latest versions it even has a feature to periodically scan your inventory and unify automatically, if you somehow obtain un-unified items. Not sure if it unifies dungeon loot like ODF does, though. And neither might not necessarily unify the output of Emasher machines, they are both mainly focused on IC2 and other mods commonly used with IC2, Thermal Expansion, Forestry, etc.
Actually there are pretty nasty threads on the Forge development forums centered on this concept. LexManos (one of the maintainers of FML) firmly states that Forge is meant entirely to be 'behind the scenes' functionality and NEVER actually supply 'in-game features', which they consider this. Team FML is of the perspective that this kind of an idea falls into the realm of "responsibility of the developers" and should be employed by mod developers and not Forge itself.
So.. this is never going to be an automatic forge feature. No 'default ores' or anything of the sort, it is going to have to fall upon the shoulders of someone else to develop a mod that does that.
While Forge/FML supplying ingot items and ores themselves wouldn't make sense, that does not preclude improving the Ore Dictionary to reduce item duplication. Some ideas: "preferred" ores, or another oredict entry type for one-to-one name:item mappings instead of one-to-many.
Currently, all Forge oredict entries are (potentially) one-to-many, in that each item name maps to zero, one, or more actual in-game items/blocks. This is what you want for wood, dyes, etc., since they are intended to be distinct in-game (so you can have acacia or redwood, or non-lapis blue dye, but still use them interchangeably in crafting/machine recipes) but ironically is not all that appropriate for ores and ingots, where you generally want to only have one of each type and any other equivalents are superfluous. If there were 1:1 oredict mappings, oreCopper etc. would map to only one item, which would make much more sense IMHO. Maybe Forge could implement an API to help with this, but it would have to be designed and implemented (and then mods adopt it), and as far as I know no one is working on it.
However, mods can already implement this functionality themselves using the existing oredict API. All they would have to do is lookup oreCopper (and so on), and use the existing item already registered there, if any. Crafting recipe inputs would not have to change since they already refer to the ores by name, but recipe and machine outputs would instead refer to the existing item instead of having the mod register its own. The duplicate item would not even have to exist at all, if an equivalent item was already registered. Sadly I don't know of any mod that does this — instead, they all register their own items used for outputs. But it is technically possible with the current Forge API.
