French: although it is my second language, it is my preferred one. I love its perpetual metaphors, its easy grammar, the beauty of the 1835 orthography (in spite of imperfections like "j" instead of "g" in many words), its potential of expressing so many things and emotions. I like its internationality, as it can suppress the problems (like in genetics). Although I have never dwelt in Canada or Switzerland or the Channel Islands, I nevertheless use huitante and heurif on a daily basis, as well as tuque, chandail, magasiner, bleuet, bouticopie, stationnement, chandail, cochambreur, goger une grippe often enough, as well as most of the so-called Belgicisms. The only thing I don't like is how Parisians (and their fans) are trying to impose their junk words to the rest of the world, and how they Anglicise their French. As for the music, unfortunately, it is a taboo. Nevetheless, I like bands like Les Trois accords, and use the Gregorian chant in French. Unfortunately, francophone metal and punk are not enough diversified or developped.
Walloon: it is, among the Romance languages, the one with the biggest Germanic adstrate. I like its grammar, because of: the supercomposed past tense; the use of the infinitive in a sentence which is coordinated with the precedent one; the substativised infinitive in a subordonated temporal sentence; the subjunctive future; its conditional sentences; the exclusive use of "to have" auxiliary verb; its various pronunciations; its Celtic substrate words; its imaginative expressions; the richness of its vocabulary; its direct way of saying the things; its similitudes with Romansh, Romanian, Lombard, and Spanish, in vocabulary and grammar. What I don't like: the phonetical and crypto-phonetical orthographic systems. Walloon deserves an etymological orthography!
Romanian: I don't like how the Academy of Bucharest created an almost artificial language, using the skeleton of the traditional Romanian language, which is spoken in Transylvania, and even in the two Moldavies. I was used with books of the 19th century. I like very much in Romanian the endless phrases, made of many sentences. I like the vocalic harmony (as observed in Transylvania), the palatalisations (the more, the better), the rhotacism. I like the phrases begining with the predicate, the attribute adjectives falling always after the noun. I am fond of the many borrowings from Hungarian, which allow you to use agglutinative words in a Romance language.
Romansh: I am sorry that their RG did not operate as a reunion of ensembles (as in Walloon or in early ABN or in Occitan), but as an intersection of their dialects. I understand easily writeen RG, but prefer the dialect of M?stair valley when spoken. They also have huge borrowings from French and Italian, instead of building their neologisms from existant words, interdialectal borrowings etc.
Lombard: I like its variety between small dialects, as well as the common features the Alpine variants have with Romanian (rhotacism, melting of b/v), and their shared vocabulary and expressions, in spite of the breakup being of more than one millennium old. I don't like how their have transformed the ce, ci /tʃ/ sound into /ʃ/ or /ss/, and how their lost the e vowel at the end of the words.
American Spanish seems rather easy and beautiful, especially as spoken by women. I don't see many inconveniencies.
Occitan and catalan are easy to read, but I don't understand much when I hear them talk. On the other hand, I generally understand spoken Portuguese, and answer in Spanish, and they answer back in Portuguese, and so on. It seems to be peasantly charming with their phonetics.
Hungarian is a language that will still be alive in 3000 AD, because it is conservative and self-sufficient (what other language has something as beautful as marokt?vbesz?lő?). I also like its vocalic harmony. Its noun cases are difficult, but fair things are always complex. Also the absence of the verb "to have".
Unfortunately, I don't speak any Slavic or Celtic language, although there are many words I understand in both families. I hope one day I would learn a Northern Slavic language like Polish, Ruthenian, or Ukrainian. I like how they palatalise everything, and don't open much their mouth when they talk, as well as the Hungarian loanwords. Between the Celtic languages, I would have more chances, "logistically", to learn Breton, but I am scared by their phonetics and much more (I one tried to learn Welsh, and gave up). On the other hand, Scottish Gaelic seems much easier, and has a beautiful phonology (the /ʃ/, the /ɯ/). Also the absence of the verb "to have" in the Celtic languages makes them all difficult.
In English I like mostly the psalms as translated by Miles Coverdale, and the BCP majestic language. In no other language do we see such almost-pleonasms: All glory and thanksgiving be to thee [...], for that thou of thy tender mercy [...]; who, by his own oblation of himself once offered, made a full, perfect, and sufficient sacrifice, oblation, and satisfaction... But the non-sensical words we see in every-day second-hand English has nothing praiseworthy. The globbish tongue will be a victim of its own success.