That's your scenario, but not everybody is the same.
Sky subscribers can't get BT Sport for a fiver. And BT Sports don't offer a day/weekly pass.
And back to the broader point, if BT Sport didn't exist, Champions League would probably still be shared on Sky and terrestrial.
The logical evolution will be a Premier League subscription. Costing more than either, but less than both. Get the content direct from the source. Sell highlights and simulcast 'big' games on other networks, but stream every fixture, every team, every weekend. Broadcast classics (which I assume they'll have the rights for), interviews, previews and roundups. Have programming curated for each market with local presenters and focusing on whatever that market values.