To Improve the page Rank of Blog , Simple Concept is to Update it With unique Content consistently ...
Their are number Of Blogs those enjoying with good PR as you Suggested in your post too , have the Same Story ..
What are the factors that helps me gain Same or better PR ... Yes All of they are regular in posting good Content ..
What Else Should i go for getting good pr ?
Yes There is more to do like to have Link to your blog from high PR websites Relevant to your website Niche ...
Post more Informative , tutorial Type Content that helps to Users in Solving their Problem and In-back they will like you post and Possibly Link your posts or blogs for others referral from their own blog or while discussing near communities ...
More Popularity of Blog counts as Big factor to earn good PR ..
Interlink your blog post To Enhance the User Reading Experiences ...
Again, social media profiles also provide "DoFollow" links and help to increase Google page rank fast.
Be popular in your niche
Google loves fast loading web pages .
No spammy outbound links: Don’t link to spammy or untrustworthy sites throgh your blog posts . This method protects your link juice and helps to maintain the page rank.