Allow players to have proxy cards, then. It's Leagues; anything goes. Additionally, you can introduce a ban list to moderate Unlimited's potential power (for example, banning Sneasal would motivate people to use different active Pokemon.)Unlimited tournaments aren't the best idea IMHO. The league is split down the middle with people with unlimited decks and people with modified decks. It's hard on the modified players because the unlimited players have access to many unrestricted cards like Briney's Compassion, etc.
If I hold an unlimited tournament, people that don't have the old cards are put at a disadvantage. If I hold a modified tournament, some players might not be able to build a modified deck (maybe).
Have a proportionate amount of tournaments, then. Maybe for every 3 Modified-format tournaments (due to being the dominant format), run an Unlimited one. That way, both parties are happy, incentives would be provided for older players, and Modified will still have its core importance (for OP and card purchasing.)Also, if I hold an unlimited tournament, it supports people to not buy any of the new cards and just keep their old cards. I want to motivate them to buy the new cards.
If one cannot afford the cards, then they should not be playing the Pokemon TCG. I am sorry if it sounds harsh but the way Modified works, the game is an intentional money sucker. =/I do see some of that with people spicing up their modified decks with unlimited cards. I think the biggest problem is people's lack of money. You can't run tournaments or expect to sell cards for cheaper prices if people don't have money in the first place.