I thing this mod has some very good oportunities

is it possible to make an additional platform in the manner of a steel walkway ?
so there should be only possible to walk on and have some pipes and belts, so excluding all other items/buildings

It is possible but I don't see why anyone would use this version over the normal version

it is meaned as a low cost walkway to the more costlier platform which you can build everthing.
Beside i feel the cost of the platform is somewhat cheap....

I don't want feature creep. If you want this feature, feel free to make your own version of the mod with this added

The cost of the platform is balanced where it is. It's the same raw materials as normal landfill except with some of the stone replaced with iron

No problem - but thanks for you answer still