The only problem I have with cosmetic surgery and whatnot is when people do this for the wrong reasons. A lot of women I know have gone under the knife to look younger or more like the "ideal" that they're sold by the media. That, in my opinion, is unhealthy. They need to work on body image and boosting self esteem rather than stuffing plastic into their bodies, in my honest opinion. I do think, however, that there are cases in which cosmetic surgery is OK- fixing birth defects or scars from accidents, for example. But overall I think there is too much emphasis in US culture on youth and the media version of beauty, and so tons of women my age out there think they need breast augmentation, butt lifts, liposuction, etc. when what we need is to love ourselves as real women.
Body art and tattoos are an entirely different thing for most people. This is using the body as canvas to express oneself artistically. While much of cosmetic surgery has the goal of conforming to a societal ideal, body art has the goal of self-expression. Two very different things in my opinion. I know lots of people with tattoos, piercings, brandings, etc. and their body art is an expression of their loves in life, beliefs, heritage, etc. and is typically very meaningful to them. I draw and paint and do calligraphy, and I plan to get a few tattoos in the next couple years of original artwork I've done- a Celtic cross and a calligraphy passage (it's currently my signature).
Bottom line to me- God made us in His image, but I think it's OK to fix the results of birth defects or traumas and such if we can. After all, God gave us a brain to create medicine and make moral decisions about it too. As for body art- it's art. It's still generated by the same desire for self-expression. Why is drawing on the body (or piercing, etc.) so different from expression on canvas or paper?
As for not being able to take our body art with us, we buy lots of things we can't take with us- our house, cars, trinkets and clothes, collectibles... Why is spending our extra money on body art any different from wasting that money on other material things? To me, it's all about moderation and balance. Freeing oneself from attachment to material things does not necessitate living an ascetic life, and material possessions to me are all the same, whether you're collecting tattoos or fine china.