Nope.  If you run a full node, you can FIND OUT whether what is in the block chain, is "bitcoin as you think you knew it".  But that doesn't change the fact that bitcoin "out there" is what it is (that is, what the miners have been building).  As there is no OTHER bitcoin around, your full node will simply INFORM you whether the only bitcoin out there is what you thought it was (it will update), or whether the only bitcoin out there doesn't correspond to what you thought it was (it will stop).

That's about it. 

That's about as useful to use a "full telescope" to see whether the moon is still what you thought it was.  If the moon is not what you thought it was, your "full telescope" will inform you, but that won't change anything to the only moon out there.

You have no *power* by running a full node.  You only have one extra bit of information: "the only bitcoin out there corresponds to what the rule set in my full node thinks it should be".

In as much as you care about that information, you may invest in a full node to obtain that information ; in the same way that you may want to invest in a 'full telescope' to inspect the "validity of the moon".  The bit may inform you about how to invest.  But that's it.  The telescope may inform you whether to invest in moon-related assets or not.  But that's it.

You are not "at the mercy of a company" if you use its full node, because you can always check that the full node has the right header chain (you ask for it, and it can't fake it - it would need proof of work for that).  And you can check all the transactions you are interested in (your coins and payments).  That's what a SPV wallet does.  They cannot lie to you about nor the header chain, nor your transactions (Merkle tree path).   There's no way to "serve false data" to a SPV wallet.