I am doing all kinds of stuff and it's always the same. Same CTR
Most of your questions are something you need to test. But in my opinion, when a user goes on a tube site they usually see a pic of the video they want to watch and click on it. I think very few people read the text under a video. Hence why text is very small under the videos.
That being said when you trying to sell them something, I think the text is likely going to work best as long as its to the point and true to the lander/offer. A decent image/gif will just compliment to that. Hope that helps...its just my opinion.
1. Animation
2. Image
3. Headline
4. Everything else
I'm guessing you are advertising on TrafficJunky?
That's the only platform I can think of that restricts the affiliate, creatively, to a fairly small pool of creatives where you wouldn't see movement in CTR.
If you are using Exoclick (or more liberal sources)... you can test 'chat' creatives, which are guaranteed to skyrocket the CTR. Albeit, at the expense of everything else.
for adult, image owns, layout owns. thats quite good enough for now?
remember its the conversions... not so much of CTR...
refer to the top guys in the market, and study them. they are the first impressions in US UK CA AU. and this is from finch i believe =D