If you are worried about a three letter agency having the resources to be able to set up and maintain enough Tor entry guards that you are likely to use one (and enough Tor exit nodes to be able to deanonymize your traffic), then said agency is not going to be stopped by a $5 a month VPN provider.
That's not an assumption I'd necessarily make. With Tor, you're getting a "random" Tor node, weighted to favor high-bandwidth nodes and by other factors. If you choose a VPN in a trustworthy country, with a trustworthy record, then that's potentially safer. Attacks to covertly fill Tor with attacker nodes
have been done in the past (see section 5.1 for the most interesting info). Attackers don't need to get anywhere near filling Tor 50% with their nodes, since you pick random nodes all the time: just 2 attacker nodes
can be enough, though with low probability.
Also, Tor is fundamentally a centralized network: you can't be a Tor node on the mainnet Tor network without the approval of the Tor directory authorities. The authorities are run by people associated with, and using rules largely set by, the Tor Project. I don't know if I really believe this, but considering how weak Tor is compared to the state-of-the-art research and how poorly-thought-out the Tor Project's overall strategy has tended to be, I've thought that Tor could be an incredibly subtle "controlled opposition" operation. It wouldn't be necessary to control every single person in the Project, just influence things enough to make progress in less important rather than more important directions, slightly bias directory authorities in sane-
looking ways which actually help attackers, etc. (I admit that this is quite the conspiracy theory.)
The term "conspiracy theory" is itself a psyop invention, a magic expression designed to have the power of aborting any discussion just by introducing the dogmatic judgement that someone is a paranoic crackpot, thus unabler to think clearly. Apart from this, I agree on everything. In fact, if THEY CAN infiltrate and control the Tor project, why wouldn't they actually do it? If they can, be sure that they will do it - or more likely, that they've already done it.