Hi! Your board looks like auto-routed :) As people said before: 1. your components are too near the borders 2. if it's possible try another placing of components: place all the connectors by sides of the board. 3. As I said before the routing seems to be not optimal. If you'll try another components placement may be the tracks routing there will be more facilities of optimization. 4. Use decoupling capacitors with every power supply pins pairs. Try to put the capacitors on one side with the MCU. 5. You wrote about lightening protection. Use more wide power and protection nets tracks.
Message
Re: Looking for critique on board layout
2010-11-10 by Eugene