I do have a reasonable proficiency in English - my mother tongue.
After 30 years' immersion in French, I manage OK, but it is still instantly obvious to everybody that I am a foreigner.
At various times, I have attempted to learn a bit of Latin, German, Italian, Japanese, Esperanto and, most recently, Alsatian.
In none of those have I achieved more than about 5% competence.
Every time I study a language, I am struck by two things:
1. The way every language is weighed down by its own pointless complications & irregularities.
2. The surprising absence, from each language, of some elements which other languages seem to consider essential.
A quick example of both is plural forms.
English, like most other languages, has a plural form of most nouns.
Sometimes simple (cat/cats), sometimes less simple (potato/potatoes, lady/ladies, half/halves, oasis/oases) but often irregular (child/children, man/men, foot/feet, mouse/mice…).
It would be a lot easier if at least they were all regular.
Yet Japanese manages perfectly well without plural forms at all.
And so does English, when it wants to (sheep/sheep, fish/fish etc).
Did you ever have the slightest problem in transmitting or receiving any information about any quantity of fish or sheep, from none to millions?
Plural forms are a waste of everybody's time & effort.
Easily enough absorbed in early childhood, they are persistent stumbling blocks for adult learners.
Then there is Gender & Agreement.
The only way I managed to start actually talking in French at all was to deliberately ignore gender & put up with the mockery.
Otherwise I would have needed to stop & check every other word in a dictionary before using it.
And French only has 2 genders, where German & Alsatian have three...
Only by a lifetime's immersion could I possibly master the table of German genders & agreements well enough to use it faultlessly at talking speed.
You need to consider 16 possibilities every time:
Masculine/Feminine/Neutral/Plural x Nominative/Accusative/Dative/Genitive.
And to think it is pretty much pointless…
English manages OK without genders & agreement at all.
Another little example is pronouns which, even in English, mostly adopt accusative forms:
I/he/she/we/you/they hit me/him/her/you/them.
Having "you" as both nominative & accusative never caused anybody a problem, so why complicate all the others?
Fundamentally, languages are being used for two, often conflicting, missions.
1. Transmitting historical, cultural & regional values & information.
2. Communicating as widely as possible.
The cultural part requires that all the peculiarities, of as many local languages & dialects as possible, should be maintained & learned by local youngsters.
The communicating part would be better handled by a single, universal, language.
Seen from here & now, that seems most likely to be English.
Seen from elsewhere, it could well be Spanish or Chinese.
If any existing language becomes "universal", it will cause significant & justified jealousy & resentment among native-speakers of all the other languages, who will be at a disadvantage.
Indeed, the jealousy & resentment are more than likely to prevent any existing language ever becoming universal.
Which is where Esperanto comes in.
Where all other languages evolved & accumulated.
It has to be hundreds of times faster to learn than any other language.
A wonderful effort.
But it has not developed any significant usage yet & seems unlikely to do so now.
1. Came too early, before there was globalization to make it necessary & internet to make it popular?
2. Still unnecessarily complicated?
3. Just not promoted well enough?
I think there is room for a radically simpler language.
Which would aim to become a universal second language due to its utter simplicity.
One where anybody could learn absolutely all the grammar, with absolutely no irregularities, in half a day.
Leaving half a day to learn some basic vocabulary.
So in one day, we could all communicate…