Welcome back to bowling. Like you, I just returned also after a layoff and glad to be back.
There are a few balls I could suggest. Now, if you are looking for a medium-light ball, I have found success with the Roto Grip Rising Star (also posted a review). The hybrid pearl/solid cover is very clean through the heads, reads the midlane really well and I have it drilled skid/snap. This ball carries very well and love it on lighter volume especially. It's the first ball for lighter oil I have seen in a while that is more forgiving if you miss a little off the target. The Neutron Core allows for great carry. I tend to be more down the boards but can move in deeper. Great ball all around regardless if you're down the boards, a tweener, or a cranker.
For medium oil, I found the Roto Grip Nomad Dagger (also a hybrid pearl/solid cover) does extremely well. I did post a review on this too. The Rotary Core gives the ball great carry and I have thrown a ton of messengers with this ball. It's very clean through the heads, reads the midlane well and has a controlled arc to the pocket. Just be careful with it on the fresh or heavier volumes as it can be a little over/under. But once the lanes carry down a little bit, it's simply one I love to throw and its versatile with all styles.
The difference between the Nomad Dagger and the Rising Star is that the Nomad Dagger has more solid than pearl in its cover while the Rising Star is the opposite with more pearl than solid.
For heavy oil, THE ball to have in my opinion is the Storm Virtual Gravity Nano. After throwing 6-1/2 games with this on a very heavy Route 66 pattern, it had so much recovery and you don't get the lane shine quickly on it. Playing more down the boards on Route 66 (between 1st and 2nd arrow), this ball basically ignored the heads, and read the midlane extremely well. Once it hit the dry, it had a pronounced hard arc which allowed me to carry extremely well most of the night. Now, I always had issues bowling on heavy oil but this ball made it fun as I was sending messengers to kick out the 10, tripped some 8's, and keeping the pins very low. After 6-1/2 games (that is how flooded the lanes were), I ended up moving down to the Nomad Dagger and finished out strong.
Now I used to use Brunswick and Columbia 300 but found Roto Grip and Storm seems to be a much better fit personally with my style. However, don't be afraid to check out 900Global/AMF, Brunswick/MoRich, Columbia300/Track/Hammer/Ebonite or any of the other companies out there. All of them have solid lineups where you can really match yourself up well.
In any case, the best thing to do is to find a good pro shop, let them see your game and see what they recommend. Many shops now have demo balls where you can try before you buy. Just because I like Storm/Roto Grip and have built a new arsenal around them doesn't mean their balls will match up the best for what you need specifically. Good luck and let us know how you make out.