Buddy,
I have done some pretty extensive research on alternatives to traditional tenkara rods and lines. I have other rod poles including 12', 15', and 21' Heras from allfishingbuy as well as another of their 12' carbon poles plus two of their Wakata tenkara rods. First of all, any of the rods/poles there can be fished like any other tenkara rod as long as the line is suitable and lines are the big variables in any tenkara fishing situations. I have tried multiple line configurations on all my rods/poles. Essentially, you need to decide on a rod/ pole that is within your budget, then a length suitable to your most common desired fishing scenario, then the size fly(s) you plan to cast, and lastly a suitable line configuration. For example, one of my saltwater combos is a 15' Hera paired up with an 20' section of 8wt line, a 2' extension of hand twisted 0X 8lb Maxima ending in a two strand perfection loop to which I attach a 10lb Maxima tippet of about 3 to 5'. I then attach a size 2 to 1/0 Clouser to this to fish off the beach under a bridge for stripers and bluefish. To test this combo for strength I took a 5lb dumbbell out into my grassy yard and attached the tippet. I was able to lift this enough to drag it without over bending and over stressing the rod so I know I should be able to land some pretty big fish as long as I net or beach them without actually lifting them completely out of the water.The 15' rod/pole is light enough to cast with one arm but better with two and spey casts are easy. My 12' Hera with a similar setup can drag a 3lb dumbbell and the attached pic is me with a 22" puppy drum (red fish) caught on a 1/8oz hand tied chartreuse marabou jig landed with ease with this rod/pole: