Cost is number one. Ability to properly insulate another. Then there is window and door installation, not to mention plumbing, heating and electrical installation. Then you have insect concerns. Finishing options on interior. Resale and maintenance.
Then if you want to add on later, it is a whole different ball game with logs. Frame construction, well, you can do anything.
There is a huge home near me in the burbs that you would swear was a log home. It's actually a frame house with log siding. Best of both worlds.
Some folks love real log houses though. If that's what you like, go for it.
Do your research and decide what's best for you.