The group was asked to suggest phonological peculiarities specific to one's native language. Inasmuch as the non-native speakers of English in this group are better at diagramming the peculiarities of my own speech far better than I could, I'll not directly answer the question. Rather, I'll offer something slightly different.
Some 20 or 30 years ago, I read something, somewhere, that a very large number of Americans of the 1960s and 70s could speak directly of a foreign-born ascendant at least thru family stories; if not a grandparent, it would be at least a set of great-grandparents. This is a fair observation. In my own case, my father's parents were born in Norway; on my mother's side, her maternal grandfather was born in England.
The greatest period of US immigration was the 1890s until the 1920s, which marks the enactment of much more restrictive immigration laws. Millions upon millions came. This was the greatest migration in human history.
The emphasis, the pressure was to assimilate, and especially, to become fluent in English. Most of these immigrants learned their English from a book. My observation, then, is that for perhaps a majority of us Americans, the influence of 'book-English' underlies much of what we speak today. Our ancestors learned their English words in print first, and the pronunciation of these words is based on the spelling of these words. While the vowels are perverse, the consonants are rather regular. As a rule, we Americans tend to hit every last consonant as it's spelled, and not how 'real' native-English-speakers in the UK or the Southern US would treat the consonant.
R and L are treated differently in British and Southern English. 'Semivowel' seems to be the word. But for those who learned it from the book, it was a consonant, painfully learned, painfully pronounced, but given a rather full consonantal value -- and their grand- and great-grand-children follow their speech patterns.
There is no real parallel for this phenomenon in any other language. We are speaking of how the *written* representation of a language fundamentally influences the speech patterns of its speakers.  The nearest parallel might be what is happening in North Africa, where Arabic is replacing the Berber languages, but this is a long term process, not the single generation language-switch found in the US. 
If you tilt your head just so, it's possible to say that American English can be described as 'native-speaker E2L'.