You got my attention here because I've edited a few Tenney/Tenny profiles -- and I did at least one merge involving the two different spellings.
I prefer "Tenney," but I don't much like the idea of standardizing the spelling of a name when there's evidence that different family members used different spellings.
In my opinion, the most important things to do with these profiles are (1) in family generations where there is some evidence that both spellings were used, include the other spelling as an "Other Last Name" (or as a "Current Last Name," if there's evidence that the person spelled the name differently from the way their parents spelled it) to reduce the chance that duplicate profiles will be created and (2) merge duplicates.