Funeral services are a delicate thing to get right. Sounds like your Grandfather inspired the best in everyone, and they all came out to celebrate him. I've been the emcee/host for a very large celebration of life, and it is a delicate thing to navigate.
I was certainly worried about not striking the balance right. But the audience let it be known they were there to celebrate his life and were happy to laugh and clap - it was really such a nice service. He was quite a talented pianist, so we had a video clip of him a few years back (still in his 70s though) playing a particularly complex piece of work - by Chopin? I need to find the title. But anyway one hand played a different time signature to the other so it was wildly complicated sounding but he flowed up and down the piano without making a mistake. At one point he slows down and says to the audience "You may be tempted to tap your feet in time to the music, please don't try" and whirls off into another piece. As they go, it was a rather great send-off.