most people consider the use of a pass as either a money saver or a convenience.
I'm afraid that in your case - and you sound much more interested in convenience and are willing to overpay to have it - a Eurailpass won't provide either.
The four countries you are travelling in, Italy, Switzerland, France, England, are probably 3 of the 4 worst for Eurailpasses, possibly the 4 worst.
What you want with a pass is put it in your pocket, board any train, and show it when requested. No fuss, no muss.
Here are the problems:
ITALY:
Italy has two high speed train companies linking the main cities. Italo is the upstart, private, just about as fast as the other, with sleek Ferrari influenced paint, leather seats throughout, even a movie theatre coach, usually the cheaper tickets - I prefer them to the other guys. Problem - Eurailpasses are not accepted on Italo.
So you are left with the others, the government owned and run Trenitalia. They run most of the other trains throughout all of Italy, from the milk runs to the fastest high speed. Local trains, Regionale and Regionale Veloce, are dirt cheap, are at the bottom of the pile so some trains are less modern than others, and your pass would be accepted freely for travel. But the cost of a pass day is almost certainly more the cost of Regionale tickets. All the rest of Trenitalia trains, including all the high speed and InterCities levels, need passengers to have assigned seating. If you buy a normal ticket, even the very cheapest, it includes a seat. You can buy tickets for both Italo and Trenitalia on their excellent apps and be set right away so very little fuss or muss. Problem - with the Eurailpass, in addition to having paid for the pass day you need to buy a seat reservation for around 10€ per leg (change trains during the day and it is another reservation fee) which involves going into the ticket window and paying. So the pass in Italy for anything but the slowest trains is actually more expensive, often a pass day is more expensive than an inexpensive ticket, plus you have to pay for the seat, so you pay twice.
Most here never suggest a Eurailpass for Italy.
SWITZERLAND
If you stick to the lowlands in Switzerland a Eurailpass works seamlessly. There are reservations available but except for a couple of tourist trains they are rarely used, certainly not by locals, and all SBB trains are available. Problem - Eurailpasses are not accepted for travel on railways up into the mountains, and Switzerland has a lot of those. You may get a discount, usually 25%, but you still have to buy the tickets. And they use a pass day. There are several ways in Switzerland to save money with regional (the Berner Oberland Pass is one) passes and you can buy a Half Price card, so Eurailpasses are not usually recommended for Switzerland if you want to be in the mountains.
FRANCE
Probably the worst country for passes. Except for some regional trains reservations are required on all medium and high speed trains, included in the price of a normal ticket but a high extra price with a Eurailpass plus the cost of the pass day. The prices for these pass holder seat reservations varies by demand, and very a lot, and they are capacity controlled - you may be unable to get a mandatory seat reservation on a train which is still not full and selling tickets, so if you really want that one you may need to buy a ticket. International trains into and out of France run as high as 30€ for a seat reservation !! And you have to go through all that hassle.
Most people do not recommend Eurailpass in France.
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