As Rory said in the comments, it doesn't sound too out of the ordinary.
In addition to that, I will say that spinning your clutch this gradiently will wear it out faster because of the amount of time the plates are rubbing against each other. It's ideal to traverse from bite point to full engagement as quickly as you can while maintaining smooth motion.
There are many variables between cars and environments that can dramatically change how they behave. The 3 biggest I can think of offhand are:
- Torque arch through rpm
- Condition of clutch assembly
1 and 2 will affect the performance like you're talking about, but I don't think 3 would considerably.
From what I can tell, your car is a turbo diesel model, and that turbo dramatically affects the torque arch. At low rpm the turbo will not really spool (spin into a functioning range) and will not provide any increased power. Additionally, I read one thing saying that the 2014 Clio had longer gearing, which again reduces torque to the wheel. Applying the throttle and bringing the rpm will spool the turbo and cause a pretty significant spike in torque and power allowing the car to roll into motion more fluidly.
As Rory is saying, gravity is the enemy in the case of hills. If you're in a 45° slope, then ~1/2 the weight of your car (I'll round it to 800kg) is being pressed against the trans. At the bite point, your engine may provide just enough force to hold the car in place (800kg up the hill), but not enough to move forward because of the loss in friction to the plates. For a little bit, adding more force will continue to pre-load the clutch springs. Once you provide enough energy to move forward, you broken the equilibrium and inertia. Now the energy stored in the springs can also discharge and, depending on the turbo and torque arch, the car can spring into motion rather than easing into it. This can vary somewhat depending on the condition of the springs and friction plates which can bite more easily since they're all moving in the same direction now.
This doesn't happen on the flats because you're only fighting inertia, which is much weaker than gravity.