@greenbeanmachine,
Pip configurations, topsheet material which influences elasticity and grip as well as pip configuration harmonizing wirh sponge, sponge hardness, sponge compressibility/elasticity all work together to give a rubber its playing characteristics. What a rubber does varies across a wide range of impacts etc.
I hate speaking about "throw" in rubber reviews because a lot of it can depend on the stroke of the player. But in terms of understanding that pip configuration can affect the exit angle of the ball on various shots, the classic article and video on the Tenergy series is still the gold standard for understanding how exit angle can be affected by pip configuration and sponge hardness. So when people say Tenergy 05 or Dignics 05 have a high throw relative to Tenergy 80 or Dignics 80, I can understand where they are coming from because those comparisons hold sponge hardness and materials and elasticity constant and the main difference is topsheet pip configurations and length which impacts how the pips deform in response to the incoming ball and the exit angle of the ball on some shots. But I have never understood it as a gravity thing, it is always an exit angle thing and to the degree that topsheet grip and pip configuration encourages tangential acceleration to promote rotation, it is then a spin thing. But the exit angle assumes that racket angle is constant - when people swing, they are often changing racket angles and speeds etc. so things might not work the same way for different players.
Sometimes topsheets can be thicker or thinner and sponges harder or softer and these can all affect the exit angle. The main reason why hard tacky rubbers are liked so much whether boosted or unboosted is because they allow for thick impacts without the ball jumping off the paddle quickly. While the effort to produce such impacts may be higher, the exiting ball quality tends to be uniquely different vs rubbers that do not allow for such degrees of compression. That said, when such rubbers are used at relatively lower level of swing speed, the results may be underwhelming in ball quality because it is harder to engage the sponge and the pips and the topsheet to get good elasticity which will add a slingshot effect that adds speed and spin. This is especially true for unboosted hard rubbers. But the elastic effect and the slingshot effect of the rubber is extremely important for spin and speed generation at the higher levels so at that level very few players will play with anything unboosted because speed especially and spin are at a premium.
I have gone back and forth on whether I believe tacky rubbers are spinniner than non-tacky rubbers. In fact, my standard answer hiatorically has always been that non-tacky rubbers are faster and spinnier than tacky rubbers all things being equal, but that the benefit of tacky rubbers is that they hold the ball longer and allow you impart a greater turning effect on the ball which allows someone with excess power to generate more spin on higher energy contacts and with less precision - the main problemwith non-tacky rubbers is that your angle/contact needs to be precise early on thicker impacts. But for someone who swings at moderate speeds or from off the table with power, non-tacky rubbers are easier to spin with and get good speed. But for someone with enough energy and the timing to get thick impacts, the ball holding property of tacky might be of some benefit so they can impart more energy into their swing and give it rotation. Modern rubbers combine elements of both with high grip and tack for more ball holding and good sponge elasticity for more spin generation.
Long story short, I broadly agree with
@SleepyMaster that most modern rubbers allow you to play all the shots with some modifications to your stroke. I wouldn't call it racket angle, it is more stroke path and swing speed. Most modern rubbers have some element of boosting or use of good rubber materials to get some elasticity for spin that can be enhanced with boosting to improve compression.
Throw, however, is about exit angle based on pip configuration. But for each player, throw can be affected on specific balls by contact point and swing trajectory and swing speed and impact depth to the point that two players can have different opinions on the same rubber based on how they prefer to hit the ball. In fact, someone who hits the ball hard with power loops on most shots vs backspin might argue that Hurricane or Skyline has a higher throw or more arc than Dignicis 09c because he can land shots using Hurricane that he cannot land with Dignics 09c. This is what sometimes makes using the phrase "throw" so confusing.
But please, I don't see where gravity has a role in any of this that is meaningful. I can be convinced though I suspect it would be very difficult.