screed or wooden flooring?

hello everybody,

its an old house an I have just begun a suspended timber floor on the complete ground floor. I work with wood, hence my preference. I have to raise floor level 4 to 5 inches anyway.And the plumbing can run between the joists. All good.
The thing is its a lot of work as the floors are very uneven and sloped and need a lot of packing. Thats no problem but if I calculate my time plus the cost of the timber and plywood its actually quite expensive.
To get a screed done professionally would be around the same cost, and no work for me. Plumbers pipes could be laid before the pour.
If I go with screed, whats the min screed thickness for stability?
And overall, what are the pros and cons between the floor types?

Thanks a lot