missing teeth can result in the remaining teeth shifting and bone loss. the results can make eating difficult and can be disfiguring. a partial would work if all the problem teeth are located together and would eliminate shifting but bone loss is still an issue. crowns whether on natural teeth or implants are the only way to prevent it.
If you can live with 4 missing teeth, then I would do that. A crown will give the teeth a nice appearnce and allow you to maybe keep the teeth longer. A crown can come off, which means your smile looks awful and you have to incur more expense to have it put back on, that is if you don't swallow it. You can still get decay under a crown, all it takes is a tiny crack or opening at the gum. There are other less expensive ways to improve your appearance. You can have these teeth pulled and get a partial, much cheaper. Dentists are always upselling, and never give you the less expensive options.