The answer depends on who owns the property. For example, if the people who want to 'change' the road (rather than 'maintain' it in the condition it has always been in) own the land the road is on, they can make changes to the road as long as they don't defeat the purpose of the easement - make it so you can't use it. In this case, they might or might not be able to ask for you to pay for the improvements, or pay additional maintanence costs, depending on if you have a maintanence agreement among the people who use the road. In example two, several people own the land that the road passes over and one user of the easement wants to come in and widen the road and then pave it...no can do. Someone can not build a new road - or significantly change- your property. These other people usually say that there is a so many feet wide ingress/ egress easement and they have a right to do whatever they want to with the road within that easement...NO they do not. If you don't want the changes you should tell them not to damage your property and explain to them that property damage can bring on treble (3X) damages under Washington law.
The answer depends primarily on what the easement deed says (I am assuming the easement was created by a written document). The person with the right to use the easement area (road) cannot expand the scope of the use; e.g., if it is for pedestrian access, he cannot convert it to vehicle access. However, if the easement document is silent about improvements, the user of the easement likely can make improvements to the easement/road, which could include paving. He would have to make them at his own expense, unless the easement document or some sort of separate maintenance agreement says otherwise. You should have a real estate review the easement document to determine your and their rights and obligations.
PLEASE BE ADVISED: This answer and any information contained herein is not intended to be treated, and should not be construed, as legal advice. Rather, this answer is offered solely for general information purposes. This answer does not create an attorney-client relationship, nor does it create any kind of legal relationship, duty, or privilege. This attorney is licensed only in Washington.