Life Assurance: Discretionary Trust 10-year anniversary periodic charge

I am setting up two level-term life assurance policies for my wife and I, and we wish to place them in trust to avoid inheritance tax. The most common and preferred type of trust is the discretionary trust, whereby trustees are appointed to decide who benefits in the case of a claim. We each want two trustees, firstly each other, and secondly another family member in case we both die so they can split the money between our children and/or their new guardians.

However, it appears as though a discretionary trust is not necessarily free of tax due to a potential charge at every 10-year anniversary. This seems to be due if, firstly, I am seriously ill (e.g. cancer) at the 10-year anniversary, then the value of the policy is no longer negligible, but would be valued based on my health, and a charge of up to 6% on everything above the "nil rate band" (£325k) would be payable. Considering the sum we are insuring for, this would potentially be unaffordable. Secondly, if I had just died but the payout had not yet been fully paid to the beneficiaries, again everything above the "nil rate band" seems to be subject to a charge of up to 6%, but at least this is far less likely and the payout would be available to cover it.

I have alternatively considered opting for an "absolute" trust instead, whereby the beneficiaries are fixed, and in which case we would want to choose each other, to provide money for raising the children. However, in the event that both my wife and I died (e.g. car crash), the money from both policies would sit in each of our estates and the total amount (above the nil rate band for each of us) would be subject to inheritance tax of 40%, so our children/guardians would receive far less.

It is certainly not money-saving to either pay a large sum after 10 years if I'm ill, or if I die just before 10 years has passed, or to pay inheritance tax if we both die.

Is there a mistake in my understanding (something I'm missing)?
Is there a trust type which may be used to fully avoid inheritance tax and other fees on life assurance payouts?