1+2) Low ball offers can be problematic if you take the approach of just submitting as many as possible and seeing what sticks. You are going to burn your agent out because while it is not necessarily that hard to submit an offer, it does take time and effort. That adds up when done over and over. It's not that it is annoying, it's just not the best plan and your agent needs to focus on activities that make money, consistently.
Additionally, I would probably try to talk a buyer out of low balling houses that just came on the market. Even bank owned properties. It seems the banks are pricing close to what they want and do adjustments about every 30 days until it sells around the asking price.
But, lowballing a home that has been on the market for 90+ days and is vacant, estate/probate or distressed in some way can be a sweet spot.
2) Doing an ARV for every single property you want to lowball will get annoying if you expect a report and analysis. Again, this takes time and effort.
If they know the market well and can just give a range based on sqft, bed, bath, etc. That's doable. I do that for a couple investors all the time. But they also know the market and just want to double check their thoughts.
A good solution would be for your realtor to give you a dump of all sold comps in the area you are looking for property. You can get both an excel format and report with pictures.
Ask you agent to meet with you for an hour and show you how to do a few ARV's. If your market changes rapidly, have them send you updated sold data every month or so.
This way you can start figuring out ARV by yourself and you will be in a better position to work with your agent more productively.
I guarantee if you do those 2 things, your relationship with your agent will be solid.
1) Form a plan around submitting low ball offers
2) Get sold data from your agent and figure out ARV on your own.