What are the pros and cons of walking warrants vs COs? Also, what are some good schools on which bases?

Pros and Cons can be subjective between each individual. It will be important for you to understand the difference in roles that the Warrant and Officers play. From both the USACAC and US Army Website: A Warrant Officer is a self–aware and adaptive technical expert, combat leader, trainer, and advisor. Warrant officers possess a high degree of specialization in a particular field in contrast to the more general assignment pattern of other commissioned officers. Commissioned Officers are responsible for leading and training enlisted Soldiers, planning missions, and organizing the internal and external affairs of the Army.

Keep in mind that these definitions are from the Army and scratch the surface of what each do but should give you a good start at your research. Ask both Warrant and Commissioned Officers at your unit why they chose the path they chose and you will get plenty of answers which could help you make your decision.

Being a Warrant officer takes a strong commitment. As you are an E1, your quickest route into the cohort would be to fly. This is the high school to flight school method and you would be a part of the 7 week WOCS course. In order for you to become a "Walking" Warrant you are going to need to be at least an E6, have at least 3 stellar NCOERs, and get the proper letters of recommendation prior to submitting your packet to the board. Being a "Walking" Warrant takes time and commitment.

As a 13B you are in one of the feeder mos’s for 131A Field Artillery Targeting Technician Warrant.
Minimum Requirements for MOS 131A:
Be a SSG and Above. (Not Waiverable)
Be a BNCOC (All Phases) or Advance Leadership Course (ALC) graduate. (Not Waiverable)
Hold MOS 13B, 13D, 13F, 13M, 13P, 13R, 13T, 11C, 19D (with 5 years experience in a feeder MOS)
Air Force - 1A4xx, 1C5xx, 1C6xx - FA Firefinder Radar Operator
Marines - 08xx - Field Artillery
Navy - 9540 Cannon Crew Member; AG - FA Meteorological Crewmember; GM - Gunner's Mate;
OS - Operations Specialist
Base line scores of 110 for Field Artillery (FA) and Technical (ST).
Must have six (6) hours of English and 3 hours of Math from an accredited college or university.
Must have two years documented (NCOERs) Section Chief Experience in feeder MOS. (Not Waiverable)
The majority of NCOERs must reflect outstanding and exceptional duty performance ratings noted with "among the best" ratings by the Rater and "successful" and "superior" ratings by the Senior Rater.
Soldiers must be fully deployable, able to meet all physical requirements IAW AR 40-501, be able to take and pass an approved APFT IAW FM-21-20 (standard or alternate), and meet height/weight standards IAW AR 600-9. Soldiers may request a waiver to take the Alternate Event APFT for entrance into Warrant Officer Candidate Program.
Have a written endorsement letter (LOR) from an interview with a CW3-CW5 who holds the 131A MOS. (Not Waiverable)
Preferred qualifications for MOS 131A for Regular Army:
Hold an associate degree or higher from an accredited college or university.
Complete the following correspondence courses on Doctrine Networked Education & Training (DOCNET)

Well it's more if you want command of people then an office or if your more interested in job specialty than WO. Promotions will be where you have more slots that puts you back in officer side. It is what you want to make of your future, so you will have to pick. Both will require furthering your education, so really both are a step in the right direction.