You may not like it - but it does not matter if you are talking about Ellen White or not - the Bible has a doctrine on prophets as we see in 1Thess 5 and 1Cor 14 etc that simply cannot be ignored.
James 2 says that the issue is "He who said" ... not "what human is being used to convey the message".
If it is determined that some message is actually from God (i.e. a true prophet) then "it matters" what you do with it. 
Nobody say "Moses was smarter than Isaiah so his writings matter more".
Also in the case of Agabus, Anna, Philip's daughters, the prophets in 1Cor 14 - nobody is saying "If God speaks to you we don't need to listen - because you are not writing scripture". David did not do that with Nathan - even though Nathan was not writing scripture and David was. 
The reason is that this is not a matter of "feelings" or "emotions" or word gimmicks - it is a matter of "HE who said" - regardless of whether Nathan writes a word of scripture - David is obligated once he is convinced that God has spoken to Nathan.
This is all pretty obvious - but if you don't stop and study the subject - it might come as a surprise.
Simply making emotional arguments does not amount to much.
in Christ,
Bob