Staying in same lab for a while after finishing PhD? I will soon defend my dissertation and been thinking on what do next after successful completion.

My situation is probably a little different than for most PhD students, since I have been working on my PhD while working full time in industry as engineer (for last 3 years). So, I have no urgent need to look for a new job after completing my PhD, unless I want a promotion (in industry) or to commit fully to research (which I been wanting to do).

If I put off doing postdoc or switching from industry to research, how would it look for me to continue working in the same lab, with same professor(s), to finish some unfinished projects or possibly get involved in recently awarded projects of my professor(s) (advisor and co-advisor)?
The original intent of the post-doc, in addition to giving a young PhD time to establish a solid publication record, was to learn and develop a new skill, technique, or research area. A few decades ago, it was not uncommon for newly minted PhDs to go straight into a TT position; today, its quite rare, making the post-doc almost assumed, and many do elect to stay in the same environment.

In my opinion, for someone who aspires to an academic career, the best post-doc is completed elsewhere: it extends one's education beyond their PhD studies into a new (but probably related) domain, builds on their research toolbox, and introduces one to a new way of thinking (avoiding so-called 'intellectual inbreeding').

However, there's nothing inherently wrong with doing a post-doc in the same lab, except that it usually doesn't offer a whole lot of opportunity to learn something new. I can think of several individuals who landed a great TT position after a post-doc in the same lab. But do consider that doing a post-doc somewhere else might make you more marketable in the long run.