Re: Time to upgrade
Unfortunately it will be difficult to get a rod that is going to knock out both bass fishing and fishing the Smokies for trout perfectly. You stated that you were interested in carp fishing and would be doing mostly bass fishing in KY.
First and foremost, where in KY? MBPhotos/Mike is one of our members who is based out of Kentucky so he might be a possible fishing buddy for you (but its a long state). There are also a lot of guys a relatively short drive from different parts of Kentucky. Jhammer, Stl_Geoff and some of the other guys have the place surrounded.
As far as rod weights go, for bass fishing and chasing your occasional carp, I would go with a 7wt. I've caught carp (and also bass) on a number of rod weights from 3-8 but for a good balance of fun, all-day castability (thats almost certainly not a word), and the ability to throw big poppers if you need to, a 7wt is going to treat you well. Personally, I prefer longer rods but thats a combination of personal preference, if you'll be fishing out of a boat often, and what the banks look like around your fishing areas. Banks choked with vegetation might warrant a shorter rod. If you only go to the Smokies once or twice a year, I would not try to balance the two types of fishing with a compromise rod. I'd get the 7wt for the fishing you'll be regularly doing and use the Martin set-up you already have until you can upgrade to a 3 or 4wt down the road.
There are a lot of rods in the more inexpensive price point that people like: Allen Xa, Echo, new Orvis Clearwater, TFO, Reddington, Rise, etc. You literally could search through this pricepoint ALL day and get hung up on 10 different rods, comparing prices and technologies and warranties, etc. The new Orvis Clearwater is a pretty good rod and has the advantage of incorporating technology that trickles down from the Helios (Orvis really stepped their game up with the new Clearwater, its much more a performer now than a pricepoint filler based on casting it the other day). Reddington is a similar situation, with trickle-down from the high-end Sage stuff. A lot of people swear by TFO. A lot of people swear by Echo (no surprise here, both the Rajeff brothers are rod-designing virtuosoes).
Personally, I fish a 7wt Allen Xa (and a 6wt Xa, and an 8wt Xa, and a 10wt Xa). I like the rod. A lot. I would happily hand this rod to anyone else to try, whether they were fishing a $60 starter rod or a $500+ rod. Its a really solid performer. It casts well, it fights fish well, it gives me power when I need it, and I don't feel like I've been casting with a piece of re-bar all day.
Most importantly, look for a good warranty and customer service. Fly rods are NOT indestructible, particularly in the hands of humans. We slip off rocks, slam car doors and trunks when we should have looked, often hold the rod where we shouldn't when fighting fish, even try to rip snagged flies out of places using techniques better suited to starting lawn-mowers or chopping wood. Basically, fly rods get broken. Sure, people go their whole lives without breaking fly rods but others don't. Others break LOTS. I know a guy that broke three in a month. He also ran over not only a rod, but a reel at the same time. Needless to say, the warranty/repairs dept. basically had him on speed-dial (for the record, it wasn't me, though I have broken a rod). I have consistently purchased from Allen because the combination of excellent customer service and a no-questions-asked lifetime warranty (and Justin, Allen's owner, has a history of being good to the people of the forum when it comes to price). Other companies offer similar service, but the moral here is don't buy a rod or reel from a place that is going to hassle you if (or when) you break it.
So that is my long-worded essay on the topic, and my personal preferences based on what I have available to me at this moment in time, but there are a lot of options out there. You'll hear all sorts of different opinions, many of which will be an inch of this or 2.54cm of that. Try and test out a rod if you can, but ultimately, you'll likely be happy with whatever you settle on, as long as you do your research. And if you're not happy, well, you can do what many fly fishermen do best: buy more.
Working out a way to convince my university to allow me to hold my TA office hours on the nearby creek...