If you use a transformer, it has to have a full rectivied output or the lights will flicker rapidly. The great thing about LED is that they don't heat up, so you can mount them in wood. I did a project some time ago with LEDs on batteries, so I found a battery holder for D cells, and wired them in series to give the proper DC voltage. Using rechargable batteries means you can run them for a long time, recharge quickly, and run again. A little microswitch somewhere inconspicuous lets them turn it off. Great little inside sign.
I'm thinking I saw some Christmas lights that had nice fat round globes about 1 inch across. I also know you can get "running" lights that seem to move in a line. That would be pretty cool too. We used to have a set of Christmas lights on a balcony overlooking the hillside below, they would change to eight different patterns. using a small controller. Drill 1/4 inch holes in a pattern and you have a pretty spectacular display. Just musing, as usual.
The more I do, the less I accomplish.