I was thinking the same on the fisheye. If the performance is the same but the Canon is "only" $50 more, I would choose the Canon. If it were $100 more...I would have to think about it.
I would go with the Canon 100mm 2.8 macro at $470, it is actually less than the Tamron before rebate, and since it has a rebate right now it ends up being less.
What about this thought, Sigma has a 150mm 2.8 macro lens, could that fit the bill for both your macro and your 135mm needs? It's a bit longer and loses some light compared to the 135mm and would be heavier than the 100mm macro, but if it is anything like my Sigma 70-200 it should be a very good, sharp lens (being a prime, I would expect even sharper).
Finally the 85mm question. If you don't reeeeaaaallly need the 1.2 aperture, I would be hard pressed to go with the 1.2 lens. If the price was only twice as much (only!), I would consider it. But from what I have read the 85 1.8 is only a little lower in the MTF charts at equal apertures compared to the 85 1.2. And since you have the 50 1.4, you already have a decent benchmark, as again from the MTF charts I have seen the 85 1.8 is just a bit below the 50 1.4 in resolution, with the 85 1.2 being in between them. I've also read that the AF is very good with the 85 1.8, that it is better than the 50 1.4, if that is of concern. I have also read that CA with the 85 1.2 and 1.8 is well controlled, but that the 1.8 version shows some purple fringe in high contrast situations. I know which lens I would buy, but you are in a different situation so this one is harder to make a good recommendation on.
BTW, I'm not sure how closely you've looked at Canon's rebate program, but it's pretty cool. The best thing is if you buy more than one item, each one will have double the normal rebate amount! Check this link http://www.bhphotovideo.com/FrameWork/R ... _condi.pdf
So if you buy the Canon 15mm fish there is a $30 rebate, and the 100mm macro has a $30 rebate, but if you buy both you would get a $120 rebate. That's some good math. :)