The Mosquito has it's share of bad characteristics. One of them is Vmc - minimum controllable airspeed for a twin. The Mosquito has a Vmc on the order of 135 knots (155 mph!). You take off at something like 100 - 105 knots. So there is a considerable amount of time accelerating when, if anything untoward happens to the engines or props, you are landing straight ahead or just dead.
It also has bad spin characteristics - a trait shared with many twins having heavy outboard engines, but not to the same degree. The vertical fin is not exactly flush with area to stop a spin or even a swing on takeoff or landing. You wouldn't normally think of spinning as a requirement for the type, but the ability to recover from one would have been VERY nice.
These factors do not mean it was less than a great airplane. No aircraft is best at everything. The Mosquito was pretty good or very good at many things, even if not the absolute best. The combination of performance made it a genuine surprise weapon, and that can never be changed.
I've read the Bf 110 was a delightful aircraft to fly at low to medium speeds, and only got to be a bit stiff at high speeds. It had many good or great characteristics. But it was no Mosquito. The Mosquito F.II maxed out at about 365 mph at all-up weight of 18,530 lbs. The Bf 110 maxed out at about 345 - 360 mph, and it would seem a good match. But the Bf 110 couldn't CRUISE nearly as fast. The Mosquito best-range was about 170 mph below 10,000 feet ... but it could cruise much faster if need be. The Bf 110 was not a fast cruiser. Both were about 20,000 pound max takeoff or slightly more, depending on variant.
I've always wondered how the mosquito might have handled with twin fins and rudders along the lines of the de Havilland Albatross. Maybe better, maybe not. I also think a scaled-down, single-engine version might have been a success. Again, maybe not. I'm glad de Havilland had the company nerve to design and proceed with a bomber that was never ordered to be designed with a specification requirement by the RAF and to do it out of a non-strategic material. Sure is a pretty plane, isn't it? So is my personal favorite DH aircraft, the Hornet.