Others have offered some nice advice on lighting.
The first image (group image) is a bit over-exposed. You've got a lot of dead-space on the right and the subjects look a bit small (also, I think they are squinting -- I try to avoid having subjects facing the sun specifically because of the tendency to squint.) Shooting with a longer focal length (even if you have to stand back farther) will help.
Your name on the photos is a bit too prominently placed. If you want a watermark or logo on an image, consider increasing the transparency (decrease opacity) and moving it to a corner.