Just curious to see what people think...Would you consider 100 Smithing with a Longbow overpowered?

Nope, but realize that means you would be the best blacksmith in the world. In other words, you have access to the greatest weapons that the living world will ever see in your lifetime. You will simply have the world's greatest longbow. I'm not sure how much damage it would do but it won't be like one-shotting dragons or anything like that. A bandit maybe.

Being just the best blacksmith won't make you overpowered. However try to stick to only blacksmithing. It's when you augment your equipment with enchanting (and being the world's greatest enchantmenter) and augmenting both of those skills with potions (being the greatest alchemist that any living being has ever seen) is when you'll be overpowered. But that should be obvious.

100 Smithing isn't overpowering. Smithing is only overpowering once you begin to fortify it with enchantments and potions then make weapons do damage of 200 or more.

As some people have said, smithing only really becomes overpowered If you couple it with another one of the crafting skills. In my opinion, the more crafting skills a character uses the more overpowered they are.

The only thing I really believe that makes smithing overpowered, is the potency of the perks. They scale in such a manner, that low-level, the perks are nearly worthless, but higher level, they throw the difficulty curve for a loop. The base skill, while certainly strong, is not overpowered in my opinion.

I'm not exactly sure what would solve the issue, without removing a lot of the viability of perking smithing.

Depends on how they use em. You can couple Smithing with Alchemy and Enchanting as long as you keep to the lower tier weapons/armor and don't "loop" them.

Yeah it does depend on whether a player just goes straight away for 100 in the skills or not. But I still think that the character will be more overpowered than one that doesn't use them

Some of the very high end weapons that already have powerful enchants on them can be over powered with 100 smithing even without perks.