As for having your ip publicly known as a bitcoin node ip, the problem might be that somebody might funnel a rogue transaction through it, and you'd be on the receiving end of govt thugs trying to find the culprit. This has already happened before. The chance is most likely miniscule for it to happen, but it's worth knowing about. Also, I'm not sure if this is implemented already, but certainly in the future, all bitcoin node ip's will be monitored, and perhaps you get an IRS-letter demanding you to declare your "bitcoin stash". This might depend on where you live as well. As the ip is linked directly to your isp-account it's straightforward to find your identity, provided you do use your real identity. I might be splitting hairs here, but I'm just saying..
It is great you want to support the network!
You can't just "funnel a rogue transaction" through someone's node because of the decentralized system. Any transaction sent to that node will be broadcast to the node's peers and thus to everyone. Hence the decentralization.
Also, I'm not sure if this is implemented already, but certainly in the future, all bitcoin node ip's will be monitored,
According to who? And by who?
Not necessarily monitored, but all nodes are listed by the getaddr.bitnodes.io project. One way to prevent monitoring or having your node publicly available is to route all node traffic through tor.