Although NO trailer out there is strong enough for a tornado, most of us veterans have had experience in one or two hair-raising storms. I can remember the DNR asking everyone to seek shelter other than your TT. Now that made me nervous. I will never forget that camping trip!! You will be fine, watch the weather, and if it looks like tornado type, don't go. (your guys do get some nasty storms!!)
Sadly for as many dry posts I have read on here I have read a equally compelling story about water intrusion, leaks and issues with water/condensation. I had a Jayco and it had a leak around the bunk door in driving rain. Luckily no real damage but the entire seal was replaced with a larger diameter seal.
Like anything else any choice in a RV is a compromise of features and design. It sounds like your family's needs fit well with a hybrid trailer. I would also look at a expandable trailer which is a hard rear slide. I believe that K-Z RV makes the Spree with king rear sliding beds and they are ultralights. The nice thing about the new Spree with the king bed is that there is no "crawling" over your mate to get out of bed. Also, if you are over 6' tall you will find many hybrids will NOT allow you to sleep stretched out.
If you decide to shop hybrids I would give some attention to the top brands like the Jayco Jayfeather and Rockwood ROO. Both brands have Internet dealers to use for price quotes and you can use their low price to bounce off a local dealer to get them to deal on $$$$. I like the ROO super-slides since they off full depth slides in a small package, the Jayco is very well built and they put a lot of detail and features standard.
Good luck and happy shopping, you will surely get some good advice on this forum.
Michael 2 DD's and my DW 6 Acre's of Maine 2009 Crossroads Cruiser CF31SB 2008 Chevy 2500HD Ext. Cab LT 4X4 Champion lil' yellow Chinese genset, 4000W Camping Pictures