what is the best software for a level designer

vvvvv

i have advanced knowledge of the Unity engine

what is the best software for a level designer.

You should ask that question in the Game Design forum. But your assumption is flawed (that the industry recognizes just ONE. BEST. ANYTHING.)

If you apply to a Unreal house, the best software is Unreal. Apply to a Unity house, and the best software is Unity.

Also what is the hiring process for such a position at studios. And lastly if anyone is recruiting a level designer please let me know i would love to get my hands dirty in a project again after all this time.

Moving this to the Game Industry Job Advice forum.

do employers consider levels that are mods good or do they like things from scratch more.

khatharr's point was, if you're strong on one, keep working with that one to build up your skills and make a portfolio.

And again, you make an erroneous assumption (that all employers behave the same, have the same preferences, wear the same color shirts, and like the exact same flavor of beer). All employers are different. Don't worry about some hypothetical employer - you have to be you. You have to develop your unique talents.

You asked "what is the hiring process." The question is rather vague. Can you narrow the question down for us? And please check this forum's FAQs. http://www.gamedev.net/page/reference/faq.php/_/breaking-into-the-industry-r16

And lastly if anyone is recruiting a level designer

We don't permit recruiting or volunteering in these discussion boards, and posts like that get deleted. If you want to jump in on somebody's indie project, check the Classifieds.

What i meant was more specifically what is the hiring process for level designer

I already said that "what is the hiring process" is a very open-ended question. You'll get better answers if we have a better understanding of exactly what you're trying to find out. If you have ever been through a hiring process, you already know what the hiring process is like (it's pretty much the same for all jobs, in and out of the game industry). Do you want someone to outline everything all the way from posting a job position to receiving resumes to filtering resumes to holding interviews to follow-up interviews to selection to job offers to first day orientation? That's a big topic!

and what do studios look for in a level designer.

They're looking for someone who clearly has mastery of the tools and the concepts of good level design, and has a strong portfolio, will fit well into the company culture, and will take off running after being hired.

The filtering of resumes

and how the interview is conducted as well as follow up interviews.

And how is first day orientation.