I agree with some of the comments already made. As part of my working life I spend a large proportion of my flying time below 500 feet, often very much below, in a twin engined turboprop.
The first few hours you do feels exciting and 'thrilling', but it does tend to become normal quite quickly. If the purpose of the low flying is for 'thrill seeking', there is a risk that you will push it as the novelty wears off.
The danger of birdstrikes is very high. I have had many close shaves but no hits at low level.
However I would also like to draw your attention to the possibility of fish strikes, yes fish strikes! I had a close shave with a large white fish dropped by a startled Gannet over the Minch (near the Outer Hebrides). This was witnessed by two others on board and the irony is we were the Scottish Fisheries Protection aircraft!
What an MOR that would have made.......
CRX