how much big should the UTHs be?!

[Seak]

Thanks alot! so in other words like the picture i post is good ey?

The pic posted looks good imo. Your snake shouldn't have any problems with those temps. 69-72 is a bit cold, so adding a UTH on the cool side (and hooking up to a t-stat of course to keep the temp decent for a cool side) would be a good idea.