I've been writing my own blog for 7 years. It still takes me at least half a day to write each of my posts (about 500 words). I post infrequently because of that. After all these years of writing on my blog, I only have a couple hundred subscribers. If I outsource it to post more regularly, would I be more efficient and effective? Probably.
The thing is, my writing is noticeably better over the years. I started out just brain dumping ideas and try to slip in screenshots whenever I can so my posts didn't look too pathetic (e.g. this one in 2008 http://www.quantisan.com/trade-of-the-day-bailed-out-of-a-wr.... Nowadays, I do the opposite. Getting your idea across simply and effortlessly for the reader is most important (e.g. this one from March, http://www.quantisan.com/more-problem-solving-less-solution-...). In recent years, my posts are getting more likes, more shares, and have been on HN a couple times.
Writing is like programming. Anyone can do it but to be good at it, you need to keep doing it and put in the effort to improve. Or, you can spend $300 for somebody else to do it for you.
1- Posts should have relevant pictures/video attached (Go to google > images > usage rights > and choose rights accordingly)
2- Make sure you read the articles afterwards to check any errors
3- Have a list of articles you want to write about each week and send them to your freelancer
4- Even better, if your freelancer can come up with ideas for your Blog posts
5- Compensate your freelancer accordingly (ie bonus if articles are really good)
6- Hire more than one freelancer if you want continuity. If one of your freelancer goes on holidays or is not interested anymore, you should have a backup ready.
So my answer is yes :)