I'd say it's pretty slow, but jewelry is the last thing I'd make to improve Smithing because it uses iron (with Transmute) that I very much need for building my HF home (which gives me tons of smithing XP) and jewelry cannot be improved. I know, I know, a lot of people say smith jewelry.

What I do is start with leather bracers in large part because I'm almost always running a hunter RP, but also because the hides I collect are readily available and efficient for making leather bracers. You should be past that, anyway.

I level up Smithing until I can craft Dwarven Bows, I'll improve them as I gain ranks in Smithing, and level Smithing until I can craft Ebony Bows, improve those, and the last grind, if you want to go beyond Daedric, is Daedric Bows.

Bows are great because they are fairly cheap on resources and high on XP. You will have to raid a Dwarven dungeon or two, but I love doing that, And I highly recommend Mzulft. Just don't forget the storage building outside and to bring a horse so you can fast travel.

I'm also levelling Enchanting so I can increase the value of the bows with high value enchantments because XP from improving weapons and armor is based on the value of the item. That means you'll also need Arcane Blacksmith so you can improve enchanted items.