Autodesk has enhanced the chamfer tool to be able to do a partial chamfer.  You will see that they have added another tab to the dialog box.

When you select either 1 or more edges it will show the below.

The To Start column is the driven dimension.  You will manipulate the length and position of the chamfer using the length of the partial chamfer and the distance to the end of the edge.  You can also have the chamfer distance and the End distance being driven from the other 2 distances respectively.

With regards to the Hole command you can now do bi-directional holes.  This has been a long time coming and once again it is an Inventor ideastation idea.  Autodesk has really made a big effort with the ideastation to let the users guide the development of Inventor.

Have you ever created a hole and then you look at the part and because it was a funny face or filleted face you found that Inventor did not cut the part properly and left a sliver of model behind?  Well worry no more.  With the extend start enhancement you are able to get rid of those irritating slivers.

When multi-bodies were introduced to Inventor it was a great leap forward.  Unfortunately you could only have the same material thickness in the multi-body.  Well in Inventor 2018 you have the ability to have multi-bodies and have different sheet metal thicknesses within each multi-body.  This is great for skeletal modelling and greatly enhances the sheet metal in Inventor.