Think about your kitchen and how you function in it.  There are a few hard and fast needs that you should consider, but you shouldn't worry about moving the fridge six inches further from the sink - and lengthening the triangle - if it means you have enough countertop space next to the fridge for you to put down the groceries when you come in from the store.  Here's a short list of considerations that may help you as you think about your kitchen's design:

• Did you leave enough space next to the fridge for your groceries? (OK, I tipped my hat early on this one)
• Do you have sufficient space on each side of the range or cooktop to put pots and utensils as you cook, or to put plates when it's time to serve?
• You'll need to leave space in front of your appliances for someone to pass by even when the door(s) is(are) open.  That is, don't put appliances right in the middle of a narrow walkway.
• You always need drawer space near your range for utensils to be used when cooking.
• Your everyday dishes and your silverware will be the things you access most in your kitchen, so consider where you're going to place them first, then decide where other items (appliances, china, stemware, and other less-used items) will be stored.

Other concerns that are appearance-based are:

• Where corners are concerned, will you use blind corner cabinets (where one cabinet is "hidden" behind another, and therefore harder to access), or will you use diagonal corner cabinets in the walls and lazy susan or easy-reach base cabinets?
• Do you want your wall cabinets to be all one height across the top, or do you like the look of a few raised cabinets for emphasis?
• Which is more important to you - to have a "perfect triangle", or to have symmetry in your door sizes?  You might have to find a happy medium between the two if your kitchen or your requirements dictate that some appliances be moved.
• Finally, if your considering an island, make sure you leave 36" - 48" of walkway between the island and your base cabinets (which are usually 24" from the wall).  A large island may look great, but if it blocks your movement in the kitchen, you'll start to like it less and less as time goes by.