It's impossible to recommend a car to someone else, much like everyone has different tastes in women/men/other.
My list at the moment if I was buying a weekend car would be as follows:
Cheap - E30 325i Sport, 968 Sport, MK3 MX5, 182 Trophy
Middle - S1 Elise 135/160, Caterham, 987 Boxster/Cayman
Top - Boxster Spyder, Cayman R, 964 Carrera, E46 CSL, Elise SC
With the excepton of possibly the MX5, they're all pretty much static or depreciating slowly. For me to have a 2nd car again, it'd have to fullfill the terms of my last ones... they have to be slightly stupid, and something I'd walk past my daily to get to on a nice day. Don't have to be the best/fastest thing out there, but just something that makes me smile.
As for the M135i. I do genuinely believe it is the best car in its price bracket, and that's simply down to BMW being so agressive with the pricing. I refuse to own a Haldex car, and I won't buy another with no manual option, as I want to make the most of owning them before they all dissapear.