1) So now I`m thinking to implement some silo elements from your example and keep interlinking web as well. Whould that bring the best of both worlds? Strong category pages and that sweet interlinking juice? What do you think BTB?
You do want to randomly interlink related articles as well as link to your category page and your powerpage as long as you are not looking like total spam when you do that.
2) You wrote that you have set your site on dedicated ip. Such thing costs starting from 150$ per month usually on most providers. Is that what you ar paying for it or do you have a cheaper solution?
I think you are thinking dedicated server. A dedicated IP runs around 2.00 or so with most hosts on a reseller program.
3) Related to previous question - from what I have red they say that if you want to rank well your loading times should not be bellow 2sec. Is that relevant from your experience? I cant really afford dedicated hosting at this point yet so this is one thing that bothers me.
Load times do matter as part of ranking a site and that is one reason I don't use a lot of plug ins, eliminate any themes I am not using in the dashboard and stay away from Hostgator, Blue Host and other hosts under the EIG umbrella for the most part.
For those articles(posts), is showing author necessary?
It is not necessary but I usually have an author showing, typically a pen name, as it does give many the sense of connecting to the owner/writer on the site. It is a tiny thing but people look to connect to other people normally and I want to give the visitor the best possible user experience on my sites as that helps conversions as it leads to trust.
Also, regarding being "active" on FB & Twitter, do i just keep on posting/tweeting things? Because i do not have any likes/followers currently..
Get likes and followers... keep tweeting and posting but start working on likes and followers. Both are fairly easy to get organically... one other thing about that. Don't buy them from fiverr or other el cheapo SEO services sites as the quality is very low and you can end up with the same group of fakes that many others get and that diminishes the quality of your account.