Yes you will get more travel, but obviously you wont be extending the shocks and coils, they will be compressed more. Bump stops are very important.
1. They prevent the shock absorbers from bottoming out. The shocks will be destroyed in no time if you allow the vehicles dynamic weight to act upon them. Shocks should not be allowed to full extend or compress, they are simply not built to cope with those stresses.
2. They prevent the coils from 'going solid'. If coils are allow to compress all the way till they cant compress any more they become a solid hunk of metal, you get a nice thump through the chassis when they do, and the coils will be permanently damaged.
3. Struts on the front are designed to extend all the way (they have their own built in bumpstops), but are not designed to fully compress. Again, they can be damaged if they fully compress under the vehicles weight.
You can play around with them to try and maximize the amount of travel without bottoming out everything, but you should follow the 1/3 rule which is the bumpstop will compress by about 1/3 of its height.