Basically, yes. Most receivers have the same shape, anyway.
They can (and actually) make smaller receivers, but when you need power at low-frequencies, the receiver has to be bigger.
The hole is already centered, placed at equal distance of every wall of your canal.
You’re right. “Classical” BTE hearing aids have no clogging problems at all. But RIC aids can help you better to understand speech. So, it is your choice.