Question - are you planning to ride the velodrome? If not, why track ends? I ask because I have been riding fix gears forever, always on road dropouts and see absolutely no reason to change. Now if you want a longer drop for making cog changes easy without messing with the chain length and you have access to the tools, make a super long road dropout.

I walk my talk. I had the bike of my logo custom made with a horizontal plate dropout made by the builder that allows any cog from 12 to 23 teeth with the same chain. (I think I can stretch that to 24 teeth and now own that cog but it hasn't seen that bike yet.) With the horizontal dropout I can easily do a sub 2 minute wheel flip, lifting the chain off with the spanner end of a Pedros Trixie fix gear wrench and dropping it on to a chain peg. I never have to touch it.

Of course I would have to have track ends if I ever wanted to be cool. (Having been riding fix gears longer than the cool crowd has been alive, I'll settle for just riding what works.)

Ben