Too smoky is definitely a creosote problem. Creosote condenses out of smoke pretty much the same way that water condenses out of steam or humid air.
The first ting to watch is how hot your fire is burning. If, when you throw on a new log, you get white billowy smoke (wbs). open the oven door and the firebox until the fire starts going good and the smoke quality improves. A little white smoke doesn't hurt anything. but when it's dense and billowy, it doesn't take but just a few minutes to ruin meat.
The other issue to watch is your oven (cooking chamber) temperature. When oven temps dip below 250*, creosote deposition increases. I know you hear a lot about 225* "low& slow" cooking, but 250* low & slow works a little better when you cooking strictly w/ wood.
There's nothing wrong w/ pecan. If you're having trouble with pecan, you'd have trouble w/ just about any wood.
Next, are you allowing your meat to come to room temp before it goes on the smoker? Cold meat attracts creosote like a cold glass attracts condesation on a hot muggy day.
Last but not least, being fairly familiar w/ Oklahoma Joe's smokers, I would suggest that given the size of the fireboxes, you might be better off to fire w/ lump charcoal and add chunks from time to time, or burn "mini-logs", you know, the ones you buy in 50# onion sacks.
As to flavor and pork, nothing beats an inject followed by a generous rub, followed by a tight plastic wrap and 24 hrs in the fridge. If you can't get flavor into your butts that way, you probably need to find a new butcher.
Hope that helps, feel free to PM me any time if there's anything else I can help you with.
