Linkjuice

Since your inner page is optimized for the particular keyword that is of interest to you, you are doing the right thing by building backlinks to this inner page. I presume the inner page is also well optimized for the keyword in question.

Why do you have to worry about link juice flowing back to the home page? In SEO, there is a huge misconception that if the inner page ranks well for a keyword, then it is easy to dethrone it.

IMHO, if an inner page ranks well, in Google's eyes, it is more relevant than any other page on your site including the home page. Hope this helps
Best
Raviv

Each page should be setup with a different keyword phrase target.

Your home page should strive to target your keyword rich domain name, presuming that your domain name was researched correctly before launch.

Here's an example.

Hot Wheel Games

Ideally my home page needs to target the keyword Hot Wheel Games.

Then I can use a free tool like Google Wonder Wheel

Google Wonder Wheel - A Wonder Tool!

To find LSI (latency semantic indexing) keywords that would relate to this keyword which I can build lower level pages for. Even better if I do research on that specific keyword using a tool like Micro Niche Finder so I can make sure that I'm building extreme value into my pages.

An important point to keep in mind is to continue building link juice to both your Index page and lower level page rather than just the lower level page or you can get penalized for not doing so.

Also... promote the areas where you are building links from for even more power. A free tool I use for that is referenced in my signature below.

Hope that helps.

Yes .......