Utility Company Wants To Update Easement

I own a house I plan on selling within the next few years. When I bought it 25 years ago there was an existing easement for an electrical transmission line crossing one side of the lot. Current line is three wires on double wooden posts about 60 to 90 feet tall. There are no poles on my land now, just wires over part of my yard.

Utility company plans on replacing the existing line with higher voltage lines replacing existing wood poles with 120 to 180 foot tall steel towers spaced farther apart. They will not promise a new bigger pole won’t be placed in my yard.

The Utility companies land agent has offered me $7500 to upgrade easement. The offer is roughly 2% of total property value. The existing easement states poles will not exceed 90 feet. The new offer has no height limitations.

1. Is 2% of property value reasonable to upgrade easement? I grew up being told never accept the first offer, do I have any chance of getting a much better offer without an attorney and an appraisal? My guess is this isn’t worth hiring an attorney.

2. Is the existing 90 foot limit give me any real negotiation leverage or not?

3. Are Utilities typically trustworthy in negotiating. The agent said new tower locations have been flagged and there are no flags in my yard so he said I most likely won’t have a pole in my yard. Can I believe there likely won’t be a new pole in my yard?

4. Where can I find data on how much electrical line easements harm property value? Google is all over the place on values.

Thank you.