some interesting still life potential there for sure. That first one, is that your braided rasta-hair or something else? lol
Like alex168, I too think that the third one is the frame that lends itself the best for sepia-toning. With a slight straightening (assuming that the window is indeed not tilted and perhaps a crop so you don't get the other side of the center, I think it would work well. Throw in some diffuse-glow on the highlights maybe, and you might increase it's impact.
As for the plant shot, I think that if you cropped out the window completely, so that you would only have the one intersecting vertical line, it would be "cleaner". It may have more impact it it was pure B&W.
The first one - due to it's complexity - doesn't lend itself to sepia I feel. This is a matter of taste of course, but rarely do I see sepias add to "textural" and macro-shots. But that's just me.
It seems to me that you have a good eye for composition though. I can almost feel what you were trying to do or almost "see" what you might've seen when you decided on these.
Thanks for sharing and I look forward to seeing more