You are not wrong…trim will let you achive 3° glideslope angle and stabilising speeds. Another point if you fly your final approach speed all the way to runway you either gonna slam and bounce or if you flare too early you will float. Mainly you need to slow down more on crossing threshold you bring down near close to stall speed on flare.
Few points from internet.
1) To avoid floating, stay on speed . Ensure you’re stabilized on final approach, and don’t be afraid to go-around if you find yourself jockeying the throttle to maintain altitude and airspeed. If you’re fast on final and haven’t already, add full flaps. Adding as much drag as possible will help negate the drag loss during ground effect.
2) Based on your landing distance, set a go-around point before you cross the threshold. If your wheels aren’t down by that point, initiate a go-around.
3) If you’re already in the round out just a few feet above the runway and still too fast, make sure to flare slowly and smoothly. Hold pitch attitude the same and let the aircraft decelerate before starting a nose-up pitch for your flare. Ballooning and floating go hand in hand when pilots try to flare as they carry excessive airspeed.
4) Don’t overfocus on your touchdown point if you’re floating. The worst thing you can do is push the nose down in an attempt to hit your touchdown point. Driving the airplane into the ground nose first can cause a prop strike, hard landing, or porpoise. Instead, just pay attention to the go-around point you’ve set.
Floating comes down to two primary factors: speed and drag. If you’re fast and in ground effect, it’ll take awhile for you to decelerate. No matter how bad you try to hit your touchdown point, the airplane naturally keeps flying since you’re well above stall speed.