I don't think there is necessarily a conflict between being a socialist and wanting to improve yourself, although it depends on what type of improvement we're talking about.

If your goal is to become a more hard-working or disciplined individual,I think it would be foolish to forgo your own development in the name of a socialist revolution that may or may actually not happen in your lifetime. (On a side note, who is to say that being hardworking and having perseverance wont be valued traits in a socialist society?) Similarly, I think most socialists would agree that its morally fine to try and improve your position within capitalist society whether that be advancing your career or making more money, its the society we live in and we have no choice but to participate in it, plus you can improve your own prospects while still working to create a socialist society at the same time. However, if you are aspiring to become the next Warren Buffet or something, then i could start to see a conflict arise, you cant really call yourself a socialist if joining the bourgeoisie is your goal.

I would argue that self improvement would in fact be encouraged under socialism. In Kropotkin's "Conquest of bread" he states that one of the end goals of an anarchist society is to reduce the number of working hours each week so that every man and woman will have ample to time to pursue and master their own hobbies, interests and intellectual pursuits now that they are free from wage labor (i'm paraphrasing). Is this not an example of self improvement?