> I heard of Palladium but the capacity for that space is so big.

There's two spaces, the smaller space (Upstairs) is 500.

Boston/Cambridge:

Brighton Music Hall is 500.

Middle East complex - Upstairs is ~200, Sonia is ~350, Downstairs is 575.

Those both host a lot of the heavier gigs that come to town in that size range.

Sinclair is ~525 but I rarely see any heavy shows booked there.

If you're tiny, O'Briens is 75 I think.

Smaller places I've seen metal shows at before in the wider area:

Worcester - Ralph's Rock Diner - ~400.

Providence - Fete Music Hall's smaller room is ~200, Alchemy - ~300.

Edit: Haven't been there, but Taffeta in Lowell is in that size range I think and has multiple metal gigs on the upcoming calendar.

You could also probably skim this listing of upcoming punk/hardcore shows in the region for venues I haven't mentioned, if they'll book that they'll certainly book metal: https://safeinacrowd.com/