Hmmm,not sure if that will be a prob or not(I think essentially the LCD will look like some capacitance but may not be a critical problem in circuit.Again,I am assuming this read of when it is daylight,is a sloppy one but probably not a good idea if the ouput is pinging the LCD).I also don't know the particulars of what you're doing with the comparator outputs(They don't have to go out ,they can be read internally and make another pin do something as well)Hey if it's no problem for you to jump to a chip with A/D and dedicate a pin,then by all means.But make sure you have laid out what you want to do and what resources you need before you get yourself in the same position again."Once is philosophy,twice is perversion"-Goethe