I feel sorry for Sheyla
Don't laugh, but think about this: Are Roslin & Adama Sheyla done right?
You may scoff at this, but I think the comparison is apt. I have watched all of BSG, sans the webisodes. That means I've seen the movie/pilot, all four seasons, the Razor movie, and the BSG prequel movie. And if we're talking ship, the comparison I'd point to is Roslin/Adama vs John/Teyla.
Why, you ask? It's simply because there was no ship AT ALL to begin with. Seriously, these guys hated each other. In the movie, he had contempt for her. At the end of s1, he had her removed from office and imprisoned. And yet, by early s4, he said 'he can't live without her'. How do you do that? And why is it relevant to SGA?
It's relevant because this is how J/T should've been developed from the beginning of s4 (without John removing Teyla from the leadership of the Athosians and putting her in the Atlantis brig). It's relevant because if it's written correctly, any two characters can become a believable pairing.
I firmly believe the writers of BSG didn't really know what they were doing in s1. But at the end of the season, they got together and said "hey, where are we headed with this". They (broadly) mapped out where they wanted to go (and refined it considerably more as they went along), including ship, and said "what do we need to do to make this work". Within half a season, these two characters had gone from 'don't let them visit each other armed' to 'hey, there might be something there between these two'.
I say this because it flumoxes me that the J/T ship could've actually been something, yet it was trampled on, just like sparky. I think sparky could've been something better, but they killed Elizabeth, so work with what you've got, right?