Weight training exercises, barbell curls pointless for a trackie?

The other stuff (legs, core) you'll get by riding your bike lots anyway. I know I get all the length strength I need by climbing whilst seated on a fixed for instance

I wish this was true...

You will not get good core strength from cycling alone. I learned this the hard way...

Cycling can and will overdevelop certain muscle groups to the detriment of others and can throw your body out of balance if your core is not strong and stable.