Mike Oldfield is another great example. He built his rep on great instrumental albums then went kind of new age/soft rock with vocals. I see he's been returning to his roots the past few years.
Actually Mike's career was a little more varied than that, but this new album is definitely a (second) return to his roots. However, Mike has been [so successful for his entire career, with multiple gold and platinum albums
he simply doesn't need to do another album ever financially. He lives in Bahamas, has multiple sets grandkids from multiple sets of wives/partners and is living the good life. I don't think he has done an album he didn't want to do since Heavan's Open and there are different periods to the music, but in my experience he has constantly been trying new things since he had the financial and contractual independence to do so, with varied success - some things I like more than others, but I don't think Mike has really ever been solidly in the pattern you describe.
The Long Instrumental Period: Tubular Bells (1973),Hergest Ridge (1974 ), Ommadawn (1975 ) and Incantations (1978 ) were all Long ( LP side length) instrumentals - most of which were multi-track recordings of Mike playing multiple instruments, most of which were acoustic
The Punk Progressive period: Platinum (1997) , QE2 (1980 ) , Five Miles Out (1982), Crises ( 1983) were mixes of long instrumental pieces short pop songs. The best way I can describe the style is a mix of Progressive rock ( YES ,Rush) with a bit of punk thrown in. A lot more emphasis on electric guitar and synth, but never dropping the accousitc instruments.
The Progressive Rock period: Discovery ( 1984) , Islands ( 1987) dropped a lot of that punkish edge and became pretty solidly progressive rock, but still continued to mix pop songs with longer instrumentals. .
The Unhappy at Virgin Records Period:
Earth Moving (1989) was the first full short song, just plain Pop Rock album, and this was towards the end of his stint at Virgin records, who where pushing him for more commercial content. I think it suffered because of it. Its very MEH.
Amarok(1990) was the result of Virgin pushing for a more commercial reprise of Tubular Bells, and Mike basically refused and gave them this - I think it is his BEST work ever - Its one continuous track , near impossible to cut up and play on the radio, and probably inaccessible to anyone who doesn't like Mike Oldfield ( a lot) already. album's back cover reads: " HEALTH WARNING – This record could be hazardous to the health of cloth-eared nincompoops. If you suffer from this condition, consult your Doctor immediately ". It was the first studio album to not even go silver You cannot place this in a genre. It is Essence of Mike Oldfield.
But the contract said he owed Virgin one more. So we get Heaven's Open by Michael Oldfield ( 1991). Its a return to the pop song with a long instrumental format. And while it has its moments, I think its the worst one he ever did. He changed the name I think in part, to distance himself from it. More Pop rock songs, but the instrumental part is okay.
And then came the " Trying Different Genre's and Styles , with some mandatory Commercial stuff to keep the Producers/Fans happy" period - which pretty much continues till this day
Tubular Bells II (1992) was that commercial revisit of the original 1973 album that Virgin wanted, but Mike did it for Warner Music (5x platnum in ESP, 2x platinum in the UK) - Probably Best described as instrumental progressive rock - with elements from the first album used in new ( and I think interesting ) ways.
The Songs of Distant Earth (1994) is the first album that plays with a New Age sort of pace and sound. I personally liked it quite a bit.. It was also an early experiment with multi media content..(enhanced CD with a simple puzzle that unlocked a music video)
Voyager (1996) is short instrumentals and entirely Celtic in genre.
Tubular Bells III (1998) is a return to a long instrumental , but is quite different in structure form the other two incarnations of TB. It was again a more commercial effort, in that Progressive Rock genre - its also the last album he has done to go Platinum ( which all the records at Warner had done till this point)
Guitars (1999) is just that - Solidly Short Guitar instrumentals. My wife still uses one of the licks as her ringtone.
The Millennium Bell (1999) was more of that long instrumental progressive rock , but composed mostly for a concert in Berlin on new years eve, 1999
Tr3s Lunas (2002) is back to being almost new age instrumentals, but they were mixed into a 1st person explorer video game environment as well as in album form. More experimentation in Media and music ,and it was interesting to wander through- after investigating certain objects, or performing a task, a new piece of music would be played. I am a little glad this isn't the only way he offered to hear it though..
Tubular Bells 2003 ( 2003) Is Mike channeling all George Lucas - he returned to Tubular Bells and re-recorded the whole thing on modern tech, 5 channel surround, the works. Sounds great. ( I don't really count this as a "new" album - its so close to the original) Is this returning to what he he became famous for? Not really. e as remastered a number of the old studio albums lately, without re-recording them. This was also the last album he did with Warner..
Light + Shade (2005) reprises a lot of the work Mike did in Tr3s Lunas, and I can't help but call this one solidly New Age. All short instrumental pieces.
Music of the Spheres (2008) Mike goes Full orchestra/classical on this one. I will put this album up against any of the great classical composers - its really that good, and will probably be the Magnum Opus Mike Oldfield is remembered for. It went Silver int he UK, but I have faith it will be "discovered" again someday
Man on the Rocks ( 2014) is all short rock songs again ( I posted one from here before) and its again quite good in my opinion.
And then Return to Ommadawn is finally coming back to rework Ommadawn, probably in much the same way Tubular Bells II was a rework of its predecessor. Amarok was heavily influenced by Ommadawn in structure, so I must say I am looking forward to hearing this new one..
Point is, Mike has continuously grown as a musician, continuously tried new things - including multimedia integration and new ways to experience music, and never really stagnated in a style - new or old. I think he drew a good blance between remaining commercially viable and trying new things. . It could be Return to Ommadawn is just another commercial product of "give em what they want" so he can put a little more cash in the bank, but Amorok taught me not to anticipate anything from an Oldfield album. Buy it, Listen to it, and see what he did now, and then decide if you like it. I hope he does do another classical piece before we loose him, because I think he really shines when he does.