MythicalFanFicGod

what I think would be crazy good for gravity powers is more precise control. I'm talking like gravity power equal to hundreds of kilograms, targeted at individual cells, the nucleus of cells, molecules, atoms, or even quarks - tearing them out of place to completely deconstruct someone's body on the microscopic level where even planet-busting strength wouldn't matter, or using gravity like Telekinesis - like having two points almost overlapping, thinner than an atom, where gravity pushes one direction, while the other point goes the opposite direction to split the bond between atoms, or even split the atoms in half to effectively sever anyone in half - since regardless of how strong you are, without a special ability, you are still made of atoms - atoms that are no stronger than another person's ones. She could also potentially break the bonds in molecules - swapping out a few atoms in one molecule for ones in others, or even do this to the Protons and Neutrons inside an atom to change the element of someone - and considering we are carbon-based beings that rely on a lot of Hydrogen and Oxygen, shifting those elements to something else - like Carbon to Boron, Oxygen to Nitrogen, and Hydrogen to Lithium - maybe even try and make a Radium atom every so often so it's like they are walking around with a small nuclear reactor inside of them - the radiation will cause harm that would take a lot longer to do otherwise. The best part is this is discreet enough that if the opponent can't sense the use of gravity powers without being hit by it, they definitely wouldn't notice since you can't feel this stuff until the damage is done.

I also thought that earlier - if they give a person up to a 100X boost, then surely it could work wonders on the sacred gears made to absorb that stuff - especially when one now has the power of a 10-winged Fallen Angel inside of it.

It's certainly not wrong. From what I've heard, just wanting to quit a job will have you all but forced into a meeting with your boss, and possibly their boss's boss, interrogating you on why you want to quit and questioning you about where you'd work and stuff, or they will do their best to not let you quit, not to mention how you're under a lot more pressure to work overtime for no pay than most parts of the world, and not doing so is practically unthinkable with how much their culture pushes you to work 'till you drop. it's bad enough that you can literally hire someone to quit your job on your behalf, and people notoriously pass out or suffer from poor health under certain jobs or companies.

Perhaps he can develop their power alongside his own - growing them to become stronger until he can use 2 boosts from each - or a boost goes from X2 to X3 power - with it becoming as powerful as the Boosted Gear when the two had Heavenly Dragon levels of power.

Combined with the fact he doubled in strength normally before, he should be 4X stronger at his max strength.

What, does the Twice Critical do 16X with balance breaker?

I agree. He could probably use the other 2 Twice Critical gears to double his adaptability to be 4X greater, then push the limits of how many boosts he can use to work on increasing them, and potentially growing in strength from the strain he'd suffer and if he might very slightly adapt to increase his base power permanently. It wouldn't be much, but if he kept on using the Boosted Gear to increases his recovery rate afterwards (10 boosts to increase it a thousand fold), he could gain some crazy strength.

I mean, as he is now, I doubt that a single Rook or Knight would be too little to reincarnate him.

Going from the fact that even after seeing it, the Fallen Angels thought Issei's sacred gear was a Twice Critical - it probably looks like the initial form of the Boosted Gear, which is slightly less bulky and less spiked than the full Boosted Gear (if I'm not mistaken.... But it could be they just never saw a picture of the actual thing, or they look identical).