At least this time round, our local lot seem to be focussing on what they will do rather than what the others won't do...last election I reached gibbering point as each candidate kept saying I should vote for them because the others were so awful...eventually, I felt like voting for the first candidate who clearly stated what he or she would do!!! I do wish they would give us credit for a little intelligence though...all this stuff promising lower taxes, more money for education, NHS whatever...but no one saying where it is going to come from. It's obvious that if you make payment increases in one area you have to make cuts in another, but they are all very quiet about that!!!
I'm not worried about the SNP...I've spent most of my life living in very rural English areas, and most political decisions seem to be made with an eye to the big cities anyway. So I'm not sure SNP getting a lot of power would make much difference to us.
If I have to choose between 'best' local candidate and 'best' party, I choose the individual every time...a local MP you can trust and respect and who will listen to your concerns is worth having. You can't do much to influence the overall party view, but you can make yourself heard to an individual.