There's something in particular that I don't like of my own manejo (mastery) of Spanish. Besides than the occasional mistakes, the tendency to double r every r that ever walked and my personal shibboleths, any words with an r/d combination such as adolorido (pained or achy), or refrigerador which constitute a veritable trabalenguas (tonguetwister) for me.
The thing that drives me crazy about my Spanish is that I can only barely "do" other accents. In English I can crack people up with my Brooklyn accent (which I come by honestly, as I'm from there and kind of had one growing up), and I can decently distinguish and reproduce (for a minute at least) lots of different accents in English. I lost my mojo for a minute for doing foreign accents in English because I taught ESL for so long and that just seems mean, but even regional American and other native English accents can be fun.
The other day I was out with two friends, one of whom was telling a story which involved repeating what a Spaniard had said to her. And ¡joder! (dayam, Spanish style), her accent (in Spanish) was perfect. I've heard other people do it, too. With Cuban and Mexican Spanish they're excellent, they can do a good Peruvian highland accent, or even the singsongy beautiful Colombian coastal one. And me? I can do nothing. Well, that's not entirely true. I can mimic a cuico (kind of yuppie) affectation. But that's not really an accent so much as a cadence and word choice issue.
Yesterday I was out taking pictures, and I ended up talking to mom who was at the park with her infant daughter. I'm more conscious of my accent lately, and was trying hard to match her rhythym and flow. I felt like it was going pretty well, and she hadn't even asked me where I was from (being polite, perhaps), when I heard the unmistakeable sos instead of eres (two different forms for the verb ser, to be, the first of which is not used in Chile). I was working so hard on mimicking her accent that I didn't even notice she was from Argentina. So I think I've found the key to working on my palette of foreign accents in Spanish.
I think I need to travel more. Or at least strike up more conversations with strangers.