This is a very personal decision and I don't think anyone could give you a definitive answer without knowing more about your specific situation.
Things to consider:
1 - does your home need improvements? If there are things that are broken or close to the end of their useful life, it may make sense to fix them.
2 - Keep in mind that it is usually very hard to recover money spent on home improvement projects. For example, if you add a $20k pool, your home value will not go up $20k. This is true for the majority of home improvement projects.
3 - how long are you planning to live in the home? If you are planning to move within the next couple of years, it may not make sense to invest in some home improvement projects. However if you are planning to stay in your home for several years, you may decide to do them and enjoy the benefits.
4 - are you upside down on your home? Depending on your current situation it may or may not make sense to put the $50k into your home.
This is not a comprehensive list. Just some thoughts that came to mind when I read your question.
I hope this helps.
Jose Dias, REALTOR
Realty One Scottsdale