1. You raise some valid points, but it's pretty common that when you lower the price for something ($ per KG to LEO) you raise the demand. The planned price drop is so severe that it becomes practical to send full weight objects into space without spending money and time on reducing weight.

2. Still a huge reduction in price. A full StarShip launch is expected to be much cheaper than a full Falcon 9 launch (per launch) because the cost is just fuel (about $300k) and some maintenance.

3. Putting legs back on for the Mars landing vehicle (a small fraction of the # starships launched btw) is totally practical.

Testing-

Yes, there is a lot more testing to go. I personally prefer testing and data-driven approvals than the traditional Paperwork based approval methods.