Job Prospects 4 years post-PhD
To fully answer a career path question will be very long. There are several questions need to be clarified first:


what do you value most in a job? Money, location, growth opportunity in the job, work-life balance, company/university culture...
why do you study biostatistics after a Ph.D.? If you want to get better pay, definitely go to industry, simply because academia is non-for-profit.
Do you have some specific research topics you want to explores? If not, it is likely you are not ready for an academic career. 


I had a similar experience. I got my Ph.D. 3 years ago and did a career change due to funding and personal reasons. I quite enjoy my current job because I am doing research in a company and don't need to worry about the funding issues.