On a side note, I feel like most of the juices I used to get a lot of flavor/feeling out of I'm just not anymore - like RY4, Strawberry, tobacco... they don't seem to DO anything to me anymore, just menthol, that's why I seem to use it so often.... I'd like to fix this situation, but I'm not sure if I'm just vaping too much, and that's why juice doesn't seem to have much of an effect on me anymore, or whether it's just that my body and tongue are just too used to the same things over and over.
First there is nothing unusual about losing your taste for a juice or any juice when it comes to vaping. There are days when everything tastes like crap to me. The best thing you can do is alternate with different flavors of juice. If you vape one juice you taste buds get used to it and it gets to where you can no longer taste the flavor.
A different battery isn't going to change that. As you said the best thing to do in your case is to try different juices and alternate during the day even if it isn't you favorite taste.
Lower ohm atomizers may give you a more flavor or it may be too much. Do not go below 2.0 ohms with an ego. An ego just doesn't have the power to handle lower ohm atomizers safely. You have to experiment and find what works for you.
I would also suggest getting a multimeter to check the ohms of your atomizers and cartridges. What they send you isn't always what it is supposed to be. You can also use it to check your battery to see if it is putting out the voltage it is supposed to when charged. On an Ego that should be at least 3.7 volts and closer to 4.2 but never over 4.2. Even though it sends 3.4 volts to the atomizer. Batteries get old and need to be replaced.