The problem with landing legs is that they are great for absorbing vertical impact and bite at absorbing horizontal impact. Of course careful landing can mitigate that some, but I have had some of those smaller legs snap off even in gentle landings. Also it can be a challenge to have your base wide enough. I counteract that by putting the telescoping legs on the most sharply inclined type of wing. (This is my kethane rover.) The wings weigh very little, and this directs the strength of the legs outwards. As someone also said, it helps to keep your center of balance low. Also, I usually don't go for the weaker landing engines because I like to play chicken with the Munar surface. That allows you to waste less fuel killing velocity at higher altitudes. Larger engines weigh more, but it is weight well spent. Also as someone said, the radial engines that you tack onto the sides of your spacecraft are just about the least efficient you can use.