Is there any particular type of serve I should pay more attention to during the practice?

If you consider the fact that for most of the pressure points (15-30, 30-40, 40-30, 0-40, 40-0, Ad-in, Ad-out) you should be serving from the Ad side, it makes sense to practice and develop a serve that you will feel confident with from this particular side.
Watch the video below for more details: