I believe God is pleased by our worship of Him wherever it takes place. There is nothing wrong with a simple church or a remodeled supermarket or the aforementioned tree.
But I also believe there is a place for the grand cathedrals, stained glass windows, intricate woodwork and stone carving and expensive fabrics.
God understands our hardwiring - He designed it! Some of us will be more receptive in an ornate and eleborate setting, and others in a plain or more natural setting.
I was raised by the Baptists: simple, inexpensive, functional. I went to visit a friend's Episcopal church in college and wept through much of the service. There in the ritual, and ceremony and architecture was a kind of worship I suddenly discovered I had been missing my wholoe life without ever knowing it existed!
That hardly means that everyone should worship in that manner or that I cannot worship in any other setting. There I found the same repetition in archiceture, stained glass and our actions (Kneeling to pray, standing to praise, sitting to learn) that is present throughout the Tabernacle. If I can recall, the metals used in the Tabernacle all had meaning, like bronze for justice and silver for mercy. (Please, someone correct me, I don't have time to check.) All of the poles that upheld the curtain around the Tabanacle grounds will bronze with a silver cap - justice with mercy - laid out visually for all to see. Wooden posts could have done the job, but not the whole job that God intended them to do.
Obviously a church can only have one style of architecture. But we need to keep in mind the different aesthetic enviroments that appeal to different people. Just as we consider those who learn best by sight, or by hearing or by doing as we make lesson plans or seek for sermon illustrations, we need to consider the varying aesthetic senses. A stark sanctuary is perfectly functional, but will it give some the sense that God is austere and stingy? Is an eleaborate setting, formal or informal, going to distract others?
