Techniques such as LIBS (laser-Induced Breakdown Spectroscopy) have been discussed at planetary conferences for a while and are, indeed, likely to appear in future missions. The ability to do stand-off examination of rocks and soils is excellent for a typical surface rover or Lander.

Be slightly cautious about how fundamental these measurements would be - you couldn't tell if a rock was sedimentary or not just from its chemistry - at least not always.

Some things are easy - a high proportion of calcium carbonate would be a hint (but beware of carbonatite lavas, which are often sodic carbonates).

Some minerals are very hard to distinguish on the basis of just their constituent elements, especially if there is some added noise from surface dust, atmosphere, etc.

So although very useful (and I'd love to be catalogueing those rocks by composition, colour, and shape), it won't tell us everything all in one go. We still have to go look close at the interesting ones...