Whilst I have been retired for quite a few years now in my 46 years working I had 25 different job titles, worked for 8 different Companies but the last Company was by far the best, I was working for myself.
I choose the hours I wanted, where I worked, what I did and how I did it.
Yes there are downsides and self discipline is paramount otherwise it goes pear shaped rapidly, but that should not be a problem for you as it is part of an Engineer’s make up. I am one myself, professionally qualified and grounded in a wide area of Engineering and vastly experience in related Building matters hence could turn my hand at a whole array of tasks.
So yes, do your own thing, but if you take my advice, keep all your irons in the fire by diversifying on what you do.
Factor in that being self employed you get no vacation pay, no sickness benefits, no company contribution to your retirement pension, no company car, no computer and no mobile phone, no expense account etc. Hence have a basic hourly rate that you charge and include in that rate what you want and put aside finances to allow for the through in incoming income. I would have different rates dependent on the contract duration and involved tasks.
Finally do look at the Tax implications, and what is the most efficient way for you to manage the tax that Bloodsuckers Inc will demand on your income. You will probably need insurance, liability and third party and possibly the setting up of a Limited liability Company through which you manage the business.