Oh forget my suggestion about the weight then. Yes, 300/305g unstrung is perfect for you, but Ezone 98 usually has a slightly too light head, so most players put just a bit of lead on the sides, at 3&9 o'clock. For example 4x5cm strips = 2g total. That helps stabilize it at impact, and also helps absorb some of the impact vibrations when you hit. If you feel that your racquet is disbalanced like that, add 2g also at the top of the handle, under the grip, where your other hand goes.
Slightly heavier helps the shoulder in an unexpected way - if you are more twitchy and explosive in movements, like Camila Giorgi for example, a too light racquet head and your fast twitch can injure you, because you're forcing it. Instead of just relaxing on serve you try to twitch hard, and that brings injury. Slightly heavier racquet slows down your motion and that often helps a lot. Also, Rev is a string that kind of requires really fast hitting, so if you change it, you might find that you're not forcing it anymore.
Also softer string is a must too, yellow Yonex Poly Tour Pro 1.25 is what most people like in the Ezone, it's a softer control poly, slightly less demanding than Rev. You could also try the thinner 1.20, it would be softer but less controlled. Softer than PT Pro - hybrid as you mentioned.
Have you tried Wilson Shift 99, also with 2g of lead at the top, or Ezone 100, that would give you more easy power, so that you don't have to work so hard. Ez98 and Ez100 are not the same thing, you should try first. Speed MP 2020 and 2022 are a bit launchy and difficult to control for a good player that likes to hit flat, and Speed Pro is a too demanding control racquet, and 18x20, very different compared to Speed MP or Ezones. Ez100 compared to Speed MP 2020/22 will have slightly more power but much lower trajectory, very different racquet.
Gravity MP is 16x19 so that's a soft controlled racquet to try, or the Tour as you mentioned, but Tour is 18x20 and will have less power than your Ezone, so try it for longer to see if you want to keep it.
A common shoulder issue in tennis is shoulder impingement syndrome, and doctors and physios often miss it. So you might mention it to them too, but the standardised mobility tests they perform to check your shoulder might not show it, because the force used when stationary is much lower compared to the force when you serve with a racquet, so it's also common that it's not diagnosed correctly.
Which movements give you pain? How is it the next two days without tennis? Can you find the painful points behind your shoulder with your thumb?
And lastly, get a Trigger Point Massage Ball, or like me, a harder version X, and softer elastic bands to massage those small tendons behind the shoulder, and to warm them up. Your physio or doctor perhaps mentioned it, but hanging yourself gently from your racquet arm in a gym or similar, regularly, before tennis, for like 2 min or so, helps the shoulder mobility a lot, together with all other stuff. Welcome to the middle age of life..
