I usually talk about the connection I have to the piece... why I am performing it... sometimes it's humorous other times it's not..
irregardless... the most important thing if you decide to speak is to keep it short and sweet. Don't have the audience tuning you out before you even start playing. Sometimes it's easy to just start rambling up there on stage and before you know it people are shifting around and looking away. It's very difficult to get their attention again after this happens.
I know lol
I like your original line--maybe add
"tonight you will hear the culmination of a lifetime spent learning how to play this amazing music on this amazing instrument. I hope you will enjoy hearing these pieces as much as I enjoy playing them. (maybe work in a thanks to your teacher here) Please silence you cell phones and thank you again."
Smile and give a quick shallow bow then while they are clapping go and sit down--when the room is silent--count to 10 in your head then take a long leisurely breath.. ( If I am nervous I silently slowly recite a poem in my head instead of counting )
there once was a lady from Eeling
who had a peculiar feeling
she lay on her back and opened the crack
then pissed all over the ceilingthe worse the nerves the nastier the limerick...lol. It works.

try it.
you can always put notes in the program and say nothing--don't feel obligated to speak.. If you start stammering it may be much harder to focus on playing.