I do most of my range practice using 130gr FMJ with my 642.
148gr WC is a good option, but some of them may have a velocity that's too low to stabilize the bullet out of a 2" barrel. I tried one brand that ended up making long, vertical tears in the target while another brand punched nice, clean holes. You may have to try a few different brands to see what works for your gun, or you may get lucky on the first one you try.
158gr SWC or LRN is another good option. The advantage with these is that most snub sights are regulated for 158gr loads.
Pretty much any load you like can be a good choice. Your current load is probably good-to-go. Try a few cylinder-fulls the next time you go to the range.
Unless your 38 is rated for +P (it should say if it is on the barrel), I'd avoid a steady diet of +P ammo. Standard pressure ammo is fine.