Howdy Mark, and Welcome to our group.
I own the exact same aircraft, 1972 7ECA w/ 115hp Lycoming. My airstrip is 1600ft usable right now, usually 2100ft, but I am doing some major reconstruction. It is not level, more like a rolling hill.
In the summer when it gets to 80F I take off with only half tanks, and use a good 1200ft to break ground, and climb out is only 300-400 feet per minute. I actually have never taken off with my wife from here as I am not really sure it would make it. I go the the local paved airport 20 miles away and pick her up there. I have trees at the end and warm days like this summer I really wish for more ponies.
Winter is another story. Breaks ground in 600-700ft, climbs 600 feet per minute. Should be no problem with a passenger, taking off from a small grass runway in cold temps. One thing I did find is that static RPM is only 2300RPM, so maybe you are getting 90hp, and less in the summer. Tried to get my propeller repitched lower, but no luck. They did not want to repitch without an overhaul. Only 1 propeller certified for that aircraft/engine combination.
My plane is relatively light, but still anemic. I plan on the 180hp conversion in the future possibly. That would make it a great performer on take off and climb, but sorry to say, no help on landing.
Hope my views help you decide.
Ken "COWBOY" Winiarski
Cowboys Air Ranch (84ME)