Agno is safer (same idea as in 'gnu'). "Anyo" is close phonetically to "anillo", that is a ring, but also a common source of jokes about little Frodo's sexuallity.
Both systems are a question of convenience, so no one is perfect. You can choose between the useful (and trendy in two or three spanish communities) "ny" or the older "gn" charged of historical context and showing lots of connections with other latin languages like french. Be aware also that "ny" leads easily to a "nll" sound that can be annoying, specially when is placed next to an 'i'.
This is just a personal opinion. Is perfecty ok if you think different, but if you are interested in mastering the second language with more native speakers in the world, I'll suggest to avoid the political experiments of the modern catalan and save yourself a lot of future headaches with grammar and orthography. To replace the 'ñ' by '~n' will work in most of the cases also.
If anyone is interested, Catalan[1] is a Latin language spoken in Catalonia and other areas of the North East of Spain, South of France and a city in Italy. It is also the official language of a country: Andorra.
It has about 10 million speakers[2], a bit more that Swedish, that is an official working language in the EU.
Its use has been forbidden in Spain during 300 years[3] -until the death of the Spanish fascist dictator Francisco Franco- but, even though it has managed to survive until today.
And there's a top level domain, .cat[4], that is intended for websites that use Catalan language.
Also, and we don't use Catalan because we are doing political experiments, or to annoy Spanish people. We use it because, for some of us, is our native language!
[1]: https://en.wikipedia.org/wiki/Catalan_language [2]: https://en.wikipedia.org/wiki/Languages_of_Europe#Number_of_... [3]: https://en.wikipedia.org/wiki/Catalan_language#Spanish_state... [4]: https://en.wikipedia.org/wiki/.cat
And I did because I think that your comment stating that Catalan language and culture are a "political experiment" is not only offensive to Catalans -and anybody a little common sense- but also shows that you have a huge lack of understanding about Spanish culture and history.