I have been researching for applying for GC through EB-3 visa category. I have a unique series of questions if anyone has gone through that scenario. Any help will be appreciated. 

You have bachelor degree from US and have been working for not more than 2 years.

Are you working in the same field in which you did your bachelor degree ? If your degree and job are not related, then you will surely get RFE in labor certification.

EB3 skilled worker is the category to apply for. Your lawyer will decide on which job deskription fits with your degree and current job during the labor certification process.

GC through EB3 has PD current for Nepal. So, your employer can file as soon as possible. However, I am not sure if you could able to complete the process before TPS expire. You will have a problem if TPS do not extend. GC processing takes 18-24 months sometimes and if you get RFE, it gets delayed further.

@neerman: Yes, I am working in the same field as my bachelor degree (Computer Science). 

HI, you are eligible for Professional Category EB3. Your lawyer will match your job deskription and salary with your experience while applying for PERM.

The only issue I see is the processing time which is almost almost impossible to catch up with TPS deadline if it does not extend for the third time.

Look at the timeline and you will know it.

step 1- PERM filling with PWD, advertisement
step 2- I 140
step 3-765 (EAD),131(AP) and 485

If your company is really in a good shape financially and have no problem with the ABT (ability-to-pay), then you can file step 2 and 3 together with I-140 premium processing (15 days window for decision by USCIS), that saves a lot of time. However, if I-140 got RFE and got denied later, all the expenses for step 3 is a complete lost. So, usually ppl do step-2 , get approval and file step 3.

It really depends on the PERM application and how your lawyer builds the Job requirements however , if you are planning to use only 2 years of experience you might get audited in PERM. I say MIGHT because i have seen a lot of people not having any problems.

The whole point of PERM is to prove that there isn't any gore workers qualified enough for the position. With only 2 years of requirement that might be hard to prove and they might set your employer AUDIT / Supervised recruitment effort.

A lawyer would be the best place to start with this. In fact you will need a good lawyer.
Also the 15 months experience you have in the current company cannot be used if its for the same position. Which means if you were a software engineer for that 15 months , the position they should be applying you CANNOT be software engineer (similar job duties.)

The 2 years of experience requirement should be a pre-requisite for the new job position.

Good luck.