1×3 : effort on the cell design, but easy frequency planning … indeed, you need good cell design (with sharp cell borders, small overlaps between cells)
adhoc : need effort on the frequecy planning, without too much effort on the cell design.
humidity, rain and other weather conditions can impact the cell coverage. if there is rain during evening, then your cell coverage is reduced during the evening.
of course, you must quantify this with drivetest, therefore you should be able to give me THE EXACT VALUE OF THE ATTENUATION in decibels. But as usual, your questions lack details.