Timber frame can be better for difficult ground as it's lighter than block and brick.
It can be an advantage not having to have internal load bearing walls if you like open plan living, which timber frame is suited to.
It is also good for tight sights. As long as you can get a crane in, you can avoid the problem of matierals all over the site.
I accept TF will cost more but if you don't have hands on building experience you are going to need a gaffer or project manager if say you are building a house that is quite big.
I see the advantages of brick and block but can also see why TF, ICF and SIPs are a good choice for the self-builder.