Personally, I do a long tail cast on for pretty much everything, unless I need to do a provisional cast on for whatever reason. I do a lot of socks that start with ribbing and with the cast on row, as you say producing a ready-made knit row, it doesn't make a difference.
So, just cast on as you usually would and start your seed stitch and you won't even notice your cast on once it's all done.
I was just looking at the various cast on videos on this site, and it looks like the alternate cable cast on might be a different one to try, if you want to. It says that it is good for K1 P1 ribbing (which isn't really all that different than seed stitch, at least not the first row). I can't say for sure though because I've never tried it.
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