I'll die on this hill but ก as g is clearly a more accurate than k. Like, you wouldn't pronounce ไก่ as "kai" (ไข่/ไหค่/etc) it's so much more clear to say "gai(lowtone)".
Point being that even the official romanization sucks.
The consonant group in question is the "velar plosives", so-called because they are produced by the sudden release of air blocked behind the tongue and the velum. In English, this includes the k and g sounds.
There are two relevant modifiers that can be applied to consonant sounds: voice and aspiration. Voice is the vibration of the vocal chords. If you touch your throat, you will feel the difference between s and z. Aspiration is the "h-iness" of some sounds, where a short burst of breath is produced alongside the consonant.
In common English dialects, the k sound is unvoiced and aspirated, whereas the g is voiced and unaspirated. The two properties go hand in hand, so either can be used to distinguish the consonants. (0)
In Thai (as I understand it), there is an unvoiced and aspirated sound, and an unvoiced and unaspirated sound. So whether these two sounds are interpreted as k/g or two varieties of k (kh/k) is ultimately arbitrary.
Pinyin, the most common romanisation scheme for Standard Chinese, went down the "k/g" route. It sounds like RTGS goes down the "kh/k" route instead.
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(0) In actual speech, this apparently clean distinction is much more blurry for a variety of reasons, but it's a good enough approximation for this purpose. For the interested you can Google "fortis and lenis".
Thank you.
And your solution works for /k/ and /kh/, but runs into problems when you have a three-way contrast (/b/p/ph/ and /d/t/th). You can't write "buu" for "crab" just because you think it sounds like an English "b"; you need "b" for the actual /b/ sound.
I don't really think it matters, no one is consistent, no transliteration covers all cases. Unless maybe ipa? (which no one uses to communicate anyway).
But it's silly to say that it's the best system just because it is easiest for people like yourself.
I do think something IPA-inspired (k/kh, b/p/ph, d/t/th) is consistent and still usable. It will also encourage better pronunciation (at least for somewhat serious students) if they are trying to say the correct sound (unaspirated /k/) instead of approximating it with an English phoneme that isn't used in Thai (voiced /g/).
But I do think that an intuitive system is better than an IPA inspired system, and that's purely because of the fact that only 1% of people will be using it and understanding it. The other 99% will be using other, random, variations. However an intuitive system will at least catch most people who speaks English.
Any romanization that is more than "close enough" is a waste of time though, when compared to simply learning to write in Thai.
I would argue that since food names are usually pronounced by non-speakers who will be unfamiliar with the romanization (or often don’t even know which language it’s coming from), the latter sort of transliteration is more useful. Egg foo young, not egg fuyung, egg furong, or daan fuyung.