Am trying to diversifyAs per my experience you have to diversify or else Google will look it as spam. So better you keep building back-links on different platforms.. hope this helps.
How about Forum Links, Profile Links and Comment links altogether. Will this help low-medium Keyword to rankIt depends on the SEO value of the blogs you're building links from.
But as the poster above said, Google may ding you for "unnatural" links due to lack of diversity
You might want to mix things up