"some of the teams rejected the terms that they were given in the past."

If some startup founders rejected 50,000 Euros and great advisers, for a 5-10% share , there is something broken in the model. At least from the pov of the (vetted, chosen) people doing the rejecting if 50,000 Euros is not providing enough value they ae well within their rights to reject it.

Fixing the broken parts may pay off more than making arbitrary rules that people have to accept whoever puts up 50k Euros. This is like saying people have to accept jobs because "we put so much effort into interviewing you". Such rules are probably unenforceable anyway and make the proposers look like idiots.