One good result of the Ukraine thing - which was, of course, horrible for Ukrainians - is that they have shown Russian power to be a Swiss cheese thing.
I think European armies are going to be purchasing boatloads of shoulder-mounted missile launchers over the next few years. Also, longer range missiles and drones capable of destroying Russian artillery. We know what they do after Georgia, Syria and Ukraine.
I am more confident than I was a few months ago that the UK can successfully repel a conventional Russian attack on our islands. We seem to be heavily invested in the kinds of technologies the Ukrainians are using and which seem very effective. And we have a modern navy and air force, albeit much smaller ones than the US. Whereas the Russian armies, while large, are equipped with disproportionate quantities of outdated tools.
I'd like to see us train young people for a year or so after school with various skills designed to support our national defence against human and viral enemies. Skills such as providing jabs and driving ambulances to information security, logistics support and use of weapons. We need to be more flexible and to engage more people in our defence, instead of simply reacting to every new threat from scratch with the same small pools of people.
All this in case NATO comes apart a bit, which hopefully it won't.