As a CT native with nothing worth hiking (this is a false statement, we have lots of fun hikes & the area around Bear Mt is even somewhat rugged but would have made a boring opening line...) but close to many mountain destinations, I've hiked in both the Catskills & ADK's.
I'm a view junkie & then a peakbagger so while I'm finally finishing the 115, (11 left all in ADK's) I've already decided I likely will not do the Cat 35 although I'm more than a third done. I do have my favorites there, Devil's Path, Hunter, Blackhead & Blackdome, Slide & Panther to name a few but bushwhacking through thick scrub to stand amongst some more trees & to check a box won't sway my mind. (I'll be surprised if I have a date next to Vly, Bearpen, Rusk or Fir.)
In the ADK, there's just a few of these, Tabletop, Esther to name a couple but they are close to fine views or combined with trips to peaks above treeline. (I'm not looking at doing Owl's head in NH 12X either)
Catskill trails, the Cloves, the streams are all neat, (Devils Path among the hardest of travereses) a couple of the roads are almost as scenic as Route 73 also, just with less cliffs. You don't get the dramatic rock filled views but the ones you get are quite nice. I'd say they are more reminiscient (sic?) of views you'd get in Southern VT or the Taconics or the southern ADK's. (Hadley, Crane).
The Catskills would be a good alternative for a foliage hike based on the types of trees you'll see. (Although the higher peaks will still be firs and spruce close to you.) You're closer to the maples on the valley floor in the Catskills than you are from Whiteface or Giant.
Personally, I wrestle with the whole, Whites Vs. Adirondacks comparison even though I've been to NH dozens of times (maybe a 100) more. I've been up all the NH peaks more times than I've been on Gothics or Haystack both of which may have the best views outside of Baxter State Park.
There is no place in the Catskills like Chapel Pond or the Ausable Lakes. (They are neat to see from the Southern Taconics on a clear day, truly impressive rising above the Hudson valley) I've heard they may be more impressive by boat along the Hudson. Some of the best trout fishing in the east can be found in the Catskills too.