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If you have distortion around the clips, then the clips are too tight on the primary. You can loosen the clips a little without compromising the mirror's safety. You might like to place something soft between the clip and mirror to cushion the grip.
The one problem with most newtonians (I'm assuming your's is a newt.) is thier fast focal ratio, anything from f/6 and lower in number is fast. This makes most newtonians to be considered by some not to be 'good' planetary scopes. Refractors and cassegrains have typically slower f/ratios. This serves to reduce glare on bright objects, in the same way a diaphram does in a camera.
The solution is just like that in a camera- stop down your newtonian.
It is a 'trick' more commonly done with big dobs to have a secondary opening to the primary so that the fast newt. becomes a slow newt. You can do this by getting your hands on a waxed vegie box from a fruit and vege shop, open it out and cut a panel that will cover the opening of your scope. Then it is a matter of cutting out a circle in this panel to give you an effective f/ratio of anything slower than f/10.
You can have this cut-out sit between the vanes of your spider so you don't have the secondary casting a shadow, or you can take the secondary into consideration in your apeture calculations and centre the cutout over your secondary.
The pic shows these 'off-set' holes in the mirror cover to a 20" dob.
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