The question in the Libertarian Party case is whether you're limiting monetary contributions because you want everyone to have equitable monetary "speech", or because you're afraid too much money from one individual would be similar to a bribe. To me, money isn't speech in the same way that corporations aren't people; each has some relationship to its SCOTUS-ruled equivalent, but neither is really an equal.

I don't really have a problem with the deceased donating money via their wills, provided they follow current and future FEC rules limiting the donations to allowed levels. (I don't think it needs to be said that dead people who didn't set things up in their will make suspcious donors in the same way that they're suspicious when signing petitions or voting…)