Var, I think you are confusing the responses of 'mn' with the parents of more able kids that post on the g&t board - there are also swathes of competiveness that display the anti-intellectual stance all over boards 
I recognise some of what you say, but think you are actually in vehement agreement with most posters. The op's dd is not unusual in this context, because we are all familiar with kids who know their alphabet/ read very early - and to be honest, some of those kids go on to do very well, and some don't. There is really no difference in parenting required at this point though. Really, who wants to be worried that they will lead a lifetime of stress because their child knows a few phonics before they are two?
At this point, the op needs reassurance that her dd is well within the bounds of normal (which she is - we all have kids like that, whether we actively count how many words or phonics they know - which is a leetle bit househousey for my liking, but I try not to judge
- she is nowhere near composing musical sonatas or reading war and peace)
It's not really terribly productive to perform 'my terrible life with gifted child' to the mother of a 16mo as a definitive 'this is what you have in store'.
Sure, some schools cater for gifted kids well, some don't. But at this point, the toddler may well be reading early and skip through KS1, but ultimately be a perfectly average kid.
Op, dd sounds lovely. You don't need to do anything different. Just have fun with her. You don't need at 16 mos to be fretting about discussing development. You don't need to be consulting professionals.
If you want to, sure, go ahead. There are people who have made a decent hobby out of their gifted offspring - it would undoubtedly be possibly to find experts to take your money, and a few people have managed to get additional funding and specific nursery placements, but it will cost you a lot of cash and time as most of this will be done privately before you can address things legally with the LEA. Most areas do not recognise kids as gifted until start school (although nurseries are often willing to run kids with other age groups informally - nursery requested additional support from the LA for ds but we're turned down flat as he wasn't old enough to be recognised as more able.)
But ultimately, it's all about parental guilt and how strongly we convince ourselves that it's about meeting individual potential. If you have the wallet and the time, you can limitlessly expand your child's education. (There are of course an awful lot of children who could achieve more in this context lol. Pretty much all of them!) - the real issue is that no child will ever reach their potential of course - but it's human nature to try. Those that have the money can seek opportunities in more ways that those who only have state education and large class sizes cannot. It's really parental choice, and parental ability.
Most people take a middle path and try to encourage along the way, and deal with school when issues come up. They don't try to address issues before they appear... (Yes, some gifted children do need support. Some don't. I have two that do (largely because they are 2e) and one that definitely doesn't. She never has.) have any of them reached their potential? No, of course not. 
It doesn't mean that I am writing them off.
Would it have been a nice hobby? With an unlimited fund of cash and time, absolutely. I dabble, here and there.
At 16mos, two of mine were broadly similar to the op's dd. At that point the third one was in receipt of high rate DLA and expected to be non-verbal.
Which is the most gifted? The third one, of course. The one with no speech. We call her Steven Hawking behind her back and she is expected to be a high court judge. The first was the most precocious at 16 mos (could happily perform alphabet, recognise letters and letter sounds in isolation, knew what words started with which letter, could count and understand numbers to ten in three languages) is actually on paper the least gifted of the three, although all fall into the notionally gifted spectrum. The performing one
is also the one that needs no support at all. Never has.
The other two slow-burners have caused me more of the problems on your list. 
At 16mos? Chillax.