Indecisive 2.4 petrol engines or D5 (185 hp) for the city (V70II)?

Now just before the final purchase decision, I doubt. I wanted a V70 II D5 with 185 hp so far. I drove and everything is good. Now I mainly drive short distances in the city and only 2 -3 times a month times 50 kilometers at a time. I like the diesel engine and the consumption in the city (but not the taxes to be paid and I drive only about 15000km a year). Now the engine does not reach almost its optimal operating temperature with my driving mode. As I understood it would therefore be useful (even in the summer) to run the stationary heating (if available) before driving. If the question is whether a petrol engine would not be “reasonable” after all… What do you think?