If I have many public ssh keys.
Is a good idea show all of my public keys in web page?
maybe a gist or similar .
my problem is : when I create a new server, I have to manually copy the keys.
yes you can share your public key, it only can be used by you and nobody else as you the only one who has private key and without that key public key is useless, so you can share with everyone it makes no difference to you if someone else got it unless you have private key.