We always have a real tree, always far too big for the house, never colour-coordinated, and invariably with a slight lean once it's been up a day or two, however carefully we set it in place at the start of its time with us. The preferred place used to be at the bottom of the stairs, but this led to many a visitor crashing straight into it on the way down from the bathroom, and the rest of us having to keep our weight down to fit the very small gap we'd to squeeze through between tree and sofa. So we've put it in front of the window this year. The total lack of natural light is a small price to pay, or so I try to convince DH, who thinks he may be developing SAD.
As for decorations, we've a huge box full, collected over the years. The DC used to choose one each every December, so there's an eclectic mix to start with. Now we add to it whenever we go anywhere new. We have a gold state coach from Buckingham Palace, a windmill from Amsterdam, a bronze plated maple leaf and bear bell from Canada, red silk decorations from China, a stagecoach from the US, etc. Breakables at the top, safe ones at the bottom, so the littlies can grab at it to their hearts' content and the cat can carry on stalking round it disdainfully, tail in air, swiping the low hanging fruit.
All the homemade decorations have been lost or disintegrated over the years. The only one left is a little cardboard box, decorated with pointy-bearded Santas, bearing the message "DD2's nekliss, keep out!". DD2 is now in her mid 30s.