Dua Lipa, Betty Who, Years and Years,Walk The Moon and Ariana Grande just because I think she has a fantastic voice.
Lady Gaga, Bruno Mars, and Justin Timberlake.
@thumper1 - I would love to see all the ones on your list. Last time I saw JT was when my girls were little and we took them to see n sync!
Did OP mean “younger” like “younger than 40-45” or “younger” like “new” or “emerging”? Lady Gaga etc. are definitely younger than us, but they have been around the block… 
If JT’s musical career were its own person, it could legally buy booze. Just saying. 
@mathmom goes to the kind of shows my H & S attend together.
I recently saw Foo Fighters, who were amazing live. I also saw Brandi Carlisle (again) recently. I went to the opening of an art installation where Sigur Rós performed … that was, um, interesting.
I would like to see Lady Gaga.
I am done seeing the older bands. Tickets cost a fortune, and I just haven’t felt the recent shows I saw were worth it. H & I love AC/DC, but we were underwhelmed when we saw them last year; same with Jeff Lynn’s ELO. The old guys are pretty much phoning it in. (Although I have heard that Paul McCartney still gives a show worth seeing - I’m just not that into his music to want to spend the big bucks to see him.)
I really enjoy seeing bands that are not “big.” They cost less, you can get closer to them, and they put on a good show - they are trying to make it in the music world, so they seem to try harder than many established acts.
I’d love to see Foo Fighters. They are one of my favorite bands. And Springsteen - I’m sure he counts as older but I’ll go to his concerts even if he’s in a wheelchair, walker or hospital bed.
“Olds” I have seen in the last year or so include Springsteen, U2, and The Pretenders. None of them were phoning it in.
I saw Miley Cyrus when she was Hannah Montana because I had preteen girls. She was a very good performer but it was the strobe lights that did me in.
This summer I saw the Eagles, who are older than old, but Vince Gill and Deacon Frye made it new again. Truly one of the best concerts I’ve ever been to. I’m now a big Vince fan and even have a Christmas CD going in my car.
@thumper1 has it. Bruno Mars has to be the “next” Michael Jackson, Prince – so much talent.
On his last tour Springsteen was back to his four hour gigs. Not phoning it in.
Can’t do the Eagles anymore. Just not the same to me.
Petty was great the last tour.
And an old fart like Mellencamp keeps everything fresh – he reworks every song for his tours. He himself says he would get bored singing the same old thing.
Does Adele count? I saw Sam Smith last year.
I’ve been going to last chance concerts this year. (Last chance they and I will be in the same place at the same time.) NGDB, Emmylou, Roger McGuinn and Chris Hillman, Brian Wilson. Nobody was phoning it in. I love to see people with that level of expertise and experience play. The only new artist I’ve been interested in is Dean Lewis but I don’t know if he tours or how I’d find out about it if he did.
Nightwish, Ghost, Sabaton, Sonata Arctica, Delain. Wait, I have seen those recently…
There aren’t any newer artists that I am interested in(except a few contemporary Christian), but there are a lot of the legends that I would love to see, if I could afford it.
Honestly, I thought they were better than I’d ever seen them (several times in the 70’sand 80’s; my previous ‘Best Concert Ever’ was Pure Prairie League, Linda Ronstadt, and the Eagles). They are too old to talk on stage so they just play and play. Vince and Deacon are great. The people sitting in front of me were Eagles groupies and had seen them dozens of times in all different venues (and they were much younger than me so were Eagles circa 1990’s people). There were some issues with our seats (blocked view, baseball backstop nets left up) and we were all pretty disappointed (except the upside was that a lot of people moved their seats so we had a ton of room). About halfway through the guy turned to me and said “This is so fantastic that I don’t even care about the seating issues any more.” We all felt that way. It really was one of the best concerts I’ve ever been to.
The opening act was Jimmy Buffett, who I’ve seen dozens of times, and while he was good and it was fun, he has aged and I’m fine if I never see him again. I’ll just go live in one of his 55+ communities…
@twoinanddone I hear you. I’m sure it would be a great show. Henley on his own is great. Add Joe, Tim, and even Vince you have some mega talent - an all star band. But without Glenn Frye it’s just not “The Eagles.” He was such a big part.
“The only new artist I’ve been interested in is Dean Lewis but I don’t know if he tours or how I’d find out about it if he did.”
Artist websites and social media accounts are a great source of info. 
Lady Gaga, Bruno Mars, and Justin Timberlake. I have seen all three and they were excellent. I have seen Keith urban who is newish too. Many others. I just saw Elvis Costello and Paul Simon excellent music too
I tend not to like crowds that much, but if I were going to a concert, here are a few folks I would go see: Death Cab for Cutie, the Noisettes, She and Him, Chris Stapleton, Crystal Bowersox (actually did see her a couple of years ago),
I heard a singer/song-writer on youtube named Janileigh Cohen whom I think is terrific. I emailed her to ask if she performs in London as she is UK based, but she makes a living busking in Manchester. I would definitely go see her. I am going to try to see the Noisettes.
He ain’t young, but it would be worth seeing Van Morrison before he retires.