1. This could be the release bearing but you say it only happens on lazy changes. Mire than likely the pedal, and when you change gear 'not lazy' () then the pedal doesnt squeak as its moving faster?

2. This could be down to an engine misfire possibly your feeling the vibration of it through the clutch pedal or gearstick? Usual vibrations are DMFS but these don't have them, might also be worth checking engine mounts and bottom gearbox mount

3. Is it difficult to engage gears whilst moving or standstill. When it crunches into a reverse are you completely stopped or still rolling a little. It will always make a distinctive clicky/crunch going into reverse, but it shouldn't be too loud, out it into reverse with the engine off and youll know what i mean. As for struggling with the gears alls i can suggest is dont force it in, or you will fuck your gearbox. If possible turn engine off and pump the pedal. Your clutch could possible be on its way out.