Genghis,
Sold my C150 last month. This is how I operated the flaps.
I could keep my hand on the throttle and operate the flap - down - switch with thumb or finger. I prefered this far more than the C152 as the gate was often worn so you had to hold the switch and move to position. Otherwise it flew past what you wanted to set.
Never had a problem with flap position. Switch down - ONE, TWO seconds - release you had 10 degrees at a time.
As for the the position of the flap indicator. It was next to where you are looking (door pilar) when you are on approach - out the window. A quick glance, thats all you need. You can still look out/keep your approach picture. Looking down to the lower part of a C152 panel is far more of a distraction.
I agree 40% flap is hard work on a go around. I have done it and my Cessna would climb. It was the larger engined FRA150 with a O-240 (130hp). I generally used 30% unless I needed 40%. Go around retraction again I used - ONE, TWO and flicked the switch back.
It's like any aircraft. Difference does not make them unsafe you just need to know what the difference is compared to what you have flown before. Not to say what you were trained on was any better/safer.
Tim