For each of the two goals, our wingbacks were caught way upfield. Canvot played a careless pass for the first and that led to a goal and Richards got done for pace by on the right with Khalaili way upfield. Yes they were both mistakes bit our wingbacks were way upfield. So some of this is Sage’s fault. If we are going to play such an aggressive pressing style, we need very quick and dependable centre backs. I would drop Richards and Canvot for now and play Tomiyasu, Disasi and Chilwell as the three centrebacks. Mitchell scored our first two goals as the furthest forward and Chilwell and Khalaili were the furthest forward for the third goal. So it bears dividends but then there has to be cover. It’s a very adventurous style of football, that’s for sure!
This is a huge factor in defensive shakiness. For most centre backs there is a world of difference between defending deep, narrow and compact on one hand, and defending high, wide, and with space around you on the other. Very few can get away with the latter.
I've seen teams try what you describe, essentially one centre back and two full backs, but can't recall it ever working in the modern era. Whilst a natural full back might be more comfortable in wide areas than a centre back, they will still struggle if the back three are asked to cover the width of the pitch, as they can't take up a decent starting position against the opposition winger.
That's what did for Richards in the first half when got beaten so easily down our right. He had to go from a central position out to the wing and was still arriving after the Fulham boy had been able to receive the ball in space and turn.
I'm sure Sage has solutions in his mind. Most coaches would focus on Richards getting over to the right back spot far earlier during our attack, but that needs us not to give the ball away during build up, and to press in such a manner that the opposition gets 'trapped' on that side of the pitch when possession is turned over. All very good in theory but, as you say, a risky approach in reality.
Ultimately this is a league in which the standard of the average team is far higher than in any other. Hence, whilst a bold, risky strategy might pay dividends over the course of the season in France, it could easily be too risky in England.
I'd be surprised if Palace end up playing an aggressive pressing game successfully, whichever back three Sage settles on.