Hi Julian!
Welcome to the Pioneer Valley, and Easthampton! I am glad you found a place- Easthampton is blossoming!
As one of the club ride leaders that creates "hilly rides" I guess I am "qualified" to reply. :)
You should start by checking out the club's collection of B rides on Ride With GPS
here. The weekly B rides generally climb anywhere between 3000' and 7000'. You can also get an idea of what we ride via ride reports, if you search our website for the tag:
B ride.
I've never ridden the Sierras, so I have nothing to compare to. But, you don't have to go far to grab hills from Easthampton. In fact, just a few miles away, you can climb into Montgomery, or, into Westhampton and Chesterfield.
I am well known to club members for creating very hilly routes for our weekly club rides. Please consider joining us on a Saturday ride. The Saturday rides are "graded" more on the mileage and climbing, rather than the average speed, It sounds like you'd enjoy a B ride on a Saturday with all the hills. We are outside the general, regular riding season, but rides do pop up on the calendar and via this group e-mail as leaders have availability and the weather is reasonable. We'd love to meet you and show you some climbs! Feel free to contact me off-list with any questions- I am the Saturday B ride leader. (P.S. rides details are on our website
here).
-Tim