Nu, what if it rains? How can we keep out the bugs, bees and animals? What type of crazy "festive" holiday is this?Don't forget that Jews in other parts of the world have to contend with weather a lot more extreme than here in the Holyland.
For many Jews, the logistics of the Succot Holiday are a total nightmare if you try to observe it in an actual succah. Here in Israel it's very common for buildings to be designed with the holiday in mind. There will be uncovered terraces. In other parts of the world, there are even legal problems in having a "hut" for eating and sleeping even for just over a week. And even here in Israel, many people live in places which don't have easily available or designated succah locations. The logistics of a building, neighborhood or other type of communal succah can be a nightmare. And it also happens that sometimes here there are winds and storms that blow off the sechach, special temporary roof of the succah or the succah itself in the middle of the holiday.
Gd designed/created the Succot Holiday to remind us of the fragility of life in This World. Succot is also one of the holidays that cancels or postpones the shiva, mourning period. One is commanded to be joyful, even when a close relative has died and just been buried. The joy of the holiday overrides personal mourning. And if a family member dies and is buried during the holiday, then the shiva is postponed until afterwards. We are first Jews who worship Gd and celebrate His Holidays, then we are individuals. Our personal feelings are secondary to Gd's mitzvot, commandments.
The Succot Holiday is when we are commanded to find the Joy in All that Gd has given us.