Are you interested in casting or catching fish? There's difference, IMHO, at least when fishing moving waters. Most of the fish I caught were within 4-15 feet of me. Once I got beyond that, getting a natural drift was hard. Still and salt waters are different.
First off if you are fishing freestone streams I'm using a Tenkara rod. Varying lengths of rods and lines can create an array of options. With the Tenkara rod you have better line control and drifts through the pockets. Just my humble opinion.
Here's the thing though. When rod manufacturers design and build a rod, they don't know how each person will be fishing the rod, under what conditions, etc,, etc., etc.
SO, they have to pick SOME sweet spot, and they do know that a "trout rod" is more than likely going to be fished somewhere between 20 and 40 feet. So, they pick a weight against the flex in the rod at 30 feet of line given the rod's weight of line designation and assuming that weight of line is used.
You an defeat this by under-weighting the line for the rod, or overweighting to adjust that sweet spot for your particular normal casting distances.
This is not to say that it won't cast just fine and shorter or longer distances. It is just that they have to pick one for the rod design.....
I have a 5wt Reddington Classic Trout, 4 piece 8'6" with 5wf line. Think I said that somewhere above. Its not top of the line, but its not a bottom dweller either. I have been told it casts very good for a $150 rod by the guys at my LFS. It's what I can afford, and I like it.
Somewhere around 25' and the rod starts loading pretty good, when I make a decent cast, and continues to feel good out to 35 or so feet, about my current limit. Fishing where I do, mostly freestone streams and rivers, 30' is a long cast and it is more like 15 - 20', ala Oldfrat, and a lot of roll casting. Occasionally I will go to one of the local lake and do some still water and test my distance, but not often as I prefer working a stream or river.
A bad day fishing is better
than the good day at work to support the addiction.