I was lucky enough as a young child to see one of these working a high country farm - it was operating off a sloped runway and I was convinced it was going to crash as it landed uphill, then convinced it was going to crash after it took off after reloading due to how slowly it climbed - I can't find a definitive number, but I vaguely recall it had a take off speed that lurked around 50kt...
On the subject of top-dressers... ...I was privileged to see a turboprop equipped Fletcher FU-24 in action a couple of weeks ago, those pilots are very darn good at flying very low in hill country. Very loud and notable engine sound.
I remember seeing AirTruks operating as a kid too, they'd drive the ground truck in between the tail booms and fill it up with fertilizer through a canvas funnel. And some of the airstrips they operated out of were truly hair-raising, more ski jumps carved out of the side of a hill with a D4 than anything else.
For ugly aircraft, look up French pre-WWII military aircraft, things like the Amiot 143 (yes, that's a real aircraft, not an AI hallucination) or almost anything that Farman made, "let's put wings on an aviary!". I think the 143's main defense was that Bf110 pilots would be so distracted either boggling or laughing they'd forget to fire at it.
50 knots rotation is perfectly fine for a plane that size. A Cessna Skyhawk is certified to rotate at 55 knots fully loaded (and since the stall speed is around 40knots, for specialty take-offs like soft fields it's much lower, 50knots is more than enough).
On the subject of top-dressers... ...I was privileged to see a turboprop equipped Fletcher FU-24 in action a couple of weeks ago, those pilots are very darn good at flying very low in hill country. Very loud and notable engine sound.
https://en.wikipedia.org/wiki/Fletcher_FU-24