By all means, do not remove all the gas...alot of folks still like to cook with gas
Then it depends on the amount of electrical service you are receiving from the pole. If you need to upgrade your service, it will cost more.
I find it amazing the scope of questions that are asked. I would like to point out, we as agents get asked these types of questions all the time, and the safe default answer that comes from the attorney world is. It depends.
It is so easy to do but we hate to do it because of schedulling etc. and of course effort. So most of this is about myself except this small part: Call a contractor, have them come out for an estimate, most are free! Then you can have a really good idea of the cost it will be to you and whether or not it is worth it for you and your family to make the change.
How expensive it would be to convert to electric will depend on whether you have a 1 or 2-story home and whether you have a slab foundation or a crawl space. If you have a crawl space, the cost will most likely be less as you cn access the first floor from underneath and you don't have to disturb the wall. I hope this helps.