ILP premium is not static, that is true.
In past 10 years all the six or seven ILP for my family has been asked to top up at least once. Quantum vary from 10 - 30% of current premium. On average, I am paying 25% more premium compare to 10 years ago.

But the company will throw in some sweeteners eg higher limit a bit, add coverage for some obscure stuff etc.

I am sure there is an insurance company that can 'bao' you for everything, if you are willing to pay any amount of premium. David Beckham's legs were insured for, how much, 20 million UK pounds?