I agree. A 7' Med Heavy would be a great rod to go with the SX. I personally like Falcon Orginal rods around $100 or if you want to step up, St. Croix Avid.
Historically really light lures don't work well on baitcasters as the cast must have enough momentum and weight to take line causing the spool to turn releasing line. A spinning reel is cable of casting very light 1/8 ounce jigs all the way up to heavy 2 ounce jigs.
All solid advice^^^^^^^^^
I use different setups for cats the few times I fish for them, but my go to rigs for stripers would work fine. I like 7' MH rods from TFO and pair them with Lews BB2 reels. I also carry a couple of 7'ML Inshore rods with Lews BB1's and 2's for sandies (I can throw lighter lures with them). They too have caught stripers and big reds with no issue. I hooked a big blue cat with one of them this winter dead sticking a fluke and it was quite the challenge. It came off right at the boat.
But for one all purpose, a 7'MH with the SX should do the trick.
Also, I got a steal on some Diawa Airds a while back and put them on 7' Ethos MH rods. I have under $100.00 in each setup and we have caught several hundred sandies and some good hybrids on them with no problems yet. That Aird reel is a lot of reel for the price.