Well, first, attractive control is really not that useful (except some circumstances). Artificial grav and vector balancing is the reasonable limit in most cases - yes, not even acceleration, since Newton means that when you push your mini black hole away from you, you get pushed back, for a net movement of 0. Sticking a blob of gravity on a stick in front of you and hoping to fly away is exactly like poking a stick in a planet and jumping on the other end.
However, holding a blob of 1g above your head on Earth means you gain an additional vector, resisted by the stick for null movement, of 1g - which does mean contragravity, but does not mean thrust. You just hang there, which means your drive only has to move your mass without resisting the acceleration vector of the planet (equal resistance to local gravity comes from the grav blob).
Additional capabilities comes from the limitations on construction. Presume a half-sphere of equipment is required, with the blob in the center (we presume the center of attraction is created at a distance from the equipment for this). Now make it a full sphere and you can get fusion if your gravity pressure is good enough, and range of attraction becomes short enough at that power level to prevent everything nearby from flying towards the new reactor. If you build it via plates, and the attractant force is perpendicular to one axis of the plate, well... No fusion for you unless you get really good magfields. Contragrav with plates requires them to be on top of the structure to be lifted. Thankfully, they'll keep themselves attached. This also mean decks are perpendicular with thrust.
Some degree of inertial control is possible by counterbalancing the acceleration vectors of objects within the field.
Really Jeff, throw me so!me technobabble of the shade tree mechanic variety - no causes, just specifics of the effect that could be manipulated.

On February 21, 2018, at 9:18 PM, Jeff Zeitlin <xxxxxx@freelancetraveller.com> wrote:

Canonically, TL9 is essentially distinguished by the achievement of gravity
control technology, which (also canonically) includes both attractive and
repulsive control. This gives us floating cities (or at least floating
Imperial Palaces), air/rafts, GCarriers, et multae ceterae.

Arguendo, assume that the laws of physics do not admit of repulsive
gravitational manipulation. No floating palaces, no air/rafts or GCarriers
as we know them. You get attractive gravitational manipulation, and some
ability to do it directionally, and with controllable range. 'Blocking'
isn't possible, so no "anti-gravity screens (or walls)".

What are the effects on planetary construction, ships, vehicles, und so
weiter?

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