Is it best to niche down, or be a generalist?

[Mike Kehoe]

I'm a new full-time real estate investor, and I'm having trouble figuring out my strategy. I've developed a relationship with a mentor that does new SFH/2-4 flat development, SFH/2-4 flat fix and flips, wholesaling, BRRR strategy and even some larger syndication all at the same time. In terms of location, it doesn't matter where the investment is, as long as it's in Chicago (not the south side) or the surrounding suburbs. Historically, in my past businesses, I could be caught saying "riches are in the niches", so I'm having trouble jumping on board with his strategy. While he's successful, his strategy or lack thereof seems all over the place, and a bit overwhelming to me. If it's a good deal, he'll most likely entertain it.

As a newbie, I can't tell if I'm just overwhelmed with being in a new industry, or in fact, I don't believe in his strategy and would rather niche down. 

In your opinion, is it better to specialize, or is it better to be a generalist and make money with several different real estate investment types?