Asking a community college professor for a letter of recommendation I am applying for a master’s program and required to obtain two letters of recommendation. Originally, I asked two teachers from the private college where I got my BA, even though I did not know them very well while I was in school. I was one of those students who studied on my own and got good grades but never reached out to professors after class as I didn’t feel like I had to. 
I received a Letter of Recommendation from one of those professors, and unfortunately it seems very generic, as if it was from a template, and doesn’t mention how I am particularly prepared for my master’s thesis.
On the other hand, I have gotten to know one of my community college professors much better. I voluntarily took his research methods class after I graduated to prepare me for the research I would be doing in the master’s program. I have also seen him during office hours and with his help I am planning on presenting at a conference in the spring. He has also taught at a more prestigious school (UCLA). He has agreed that he would be able to write me a letter of recommendation. 

Would this be preferred over a more generic letter from my private college?
This is hard to weigh without knowing more information about you, but it can be addressed in a general way.

One of the biggest pieces of advice I give to undergrads is to develop a relationship with professors they hope to earn letters of recommendation from, including going out of their way to take extra classes/do extra work with them.  Now that that ship has sailed for you, I would lean toward the community college professor.

You don't mention the other letter you got from your BA institution, but I presume it's a solid one.  That allows you a little more leeway on your second letter.  You can already show strong results at the BA level, so getting a very good letter from a community college professor (or, e.g., an employer from the private sector in your field) that knows you well will look better than the generic letter.  People who read these letters know what a generic letter looks like, and are certainly able to "read between the lines" and assume this letter doesn't say much good about you.

I would be concerned if none of your letters came from your BA institution, so if my assumption isn't correct about the other letter, then I would say you probably have to use the generic one.