Re: Here's a thought
Loopholes and dodgy tax schemes are being closed all the time. There were footballers with EBTs, there was the Jimmy Carr dodge, there was the Ingenious Film investment trick. All those were closed down. Even PSC avoidance is being closed off: first with public-sector contractors prevented from avoiding IR35 (you can be certain they'll get private-sector contractors next); and the new dividend tax clobbers the rest.
Expenses are expenses: they aren't earnings. If I drive a taxi all day and claim £300 a month in petrol as expenses, that's what I've paid in petrol. It's gone, vanished; I can't spend it again on booze & hookers.
On your example calculations you've ignored National Insurance (an income tax in all but name). With an income of £100,000, you'll hand over £34,533 to the exchequer; whereas on £30,000 you'll hand over just £6,433. There's an excellent calculator at https://listentotaxman.com/
"The top 1% income is over £250k; they take home 70% of that"
Nope: they take home 57% of that. See above for calculator link. Again, you can argue that they should be taxed more; but please ensure you know what the current level is before diving into that notion.
Overall I reject the notion that we are surrounded by overpaid wastrels with too much money (except in the Premier League). Tax has a real impact on how much work people are prepared to do. If I'm an NHS surgeon earning £99,999, I'm not going to bother doing any overtime because I know every extra hour will be taxed at 62%, and at that rate I'd rather spend the time at home with the family.
Yes, I've selectively quoted the figures. Everyone does. I agree that the poor pay VAT, fuel duty, sin taxes, and of course the biggest of them all, the horribly regressive Council Tax. But at least they're paying a good chunk less income tax than they used to. That's progress.