Starting a tech blog - Some queries!

Hi!
Thank you for taking the time to read this! I actually do appreciate it!

I tend to starting a tech blog in the coming few months. And I have quite a large budget for it. So, I cooked up a strategy I'll be following and just wanted to get it past you guys to get a second opinion!

Another thing, I tend to make it a long time project and an authority site.

So, Here I go:
I was thinking about taking a very very popular keyword(I mean something as big as 'iphone apps' or 'android apps' or 'android vs iphone' and the keywords of the sort)
These keywords are very high competition and getting ranked will take a lot of investment.
But as I mentioned above, I have quite a big budget for the start-up.
And can invest in a regular extremely high quality content writers and best of the best SEO services

So, I want to ask, is this a worthwhile strategy?
I mean, will this get me somewhere or will I just be keep going around in circles and get burned out.

Please tell me your experience with starting authority sites and what you think about what I plan to do. And if you can suggest something better, I'll be very grateful

Best Regards
Asad Salman