RM 5000 is completely bullshit for a 0.2ct GIA diamond, even if it is a 0.2 Triple Excellent. Most shops don't carry 0.2ct with GIA cert though. I believe Wah Chan won't throw you such price, but if they do, it is a marked-up price, so you are expected to haggle the price. It is a total waste of time for me though because we are now in a digital age. If the price is final, then walk-out. It is too expensive.

For your budget, you can get at a standard 0.3ct GIA Triple Excellent at least.

On a side note, I can already get a 0.2ct E VS2 Super Ideal diamond from Brian Gavin Diamonds, complete with ring setting at approxiantely RM 3200. And that is a super ideal stone! With full images to prove its performance and cut quality.

One of the most affrodable way to get a GIA graded stone is to get online.

If you don't prefer online, there are also other stores running promotions, such as Tailored Jewel,  ZCOVA, and Eumayco. You can also visit iDo Jewellery. You can find all of them on Facebook.

You can read my blog on how to buy online.

1. The recommended crown angle will be between 34 to 35 (I prefer 34.3 to 35 though) for good amount of fire. For pavilion angle, preferably 40.6 to 40.9 for good amount of light return. Quickest way to weed out different diamonds is using HCA to reject poor performers - https://www.pricescope.com/tools/hca. This is a rejection tool. Don't use it to select. Another method is to use Enchanted Cut Score Calculator - https://enchanteddiamonds.com/cut-score-calculator. Just input the GIA cert number. Usually I will accept 97% and above. This tool, although is proprietary, but its scoring matches with the recommended proportions that I have provided. In fact, they are the proportions of super ideal diamonds, which are the top performers for round diamonds. In any case if they do not let you capture the proportions or the cert number, you can either leave the store, or use brain to memorize the proportions.

2. Those are different shapes. There are a variety of them, but only round brilliant gives the best performance. There are still the most famous one.  Another famous shape is Princess Cut - which is square shape diamond. There are also other proprietary cut for round, like the Hemera from Poh Kong, which cuts to 101 facets, compared to the modern round brilliant, which has 57 facets. Extra facets means extra windows to reflect light, but it is actually the same cake size being cut into smaller pieces, so the light return will be many, but tiny, causing it to look very sparkly, but will sacrifice on fire (colour sparkles/rainbow colour). Some actually prefer those tiny sparkles, while others may not. Choice is up to individual. Personally, I like to stick to the standard one because the price is more competitive and of course, I like the bolder sparks instead of tiny ones.

3. The ring (without diamond) - I usually recommend people to go to Memory Jewellery at Sentul, KL, because they give the best price range so far, and it can be as affordable as RM 750, and towards RM 1000 to RM 1500 for custom ring. Usually I will recommend the custom route to get wider ring and extra rhodium plating to get longer lasting shine. For the diamond, a good 0.2ct can look as big as a badly cut 0.3 carat. So most important is get the cut in an ideal range. And as far as whether a good 0.2ct will look small or not? I think it will be best not to think about that, instead, focus on your budget. The diamond is just part of the whole wedding thing, if it is even necessary to begin with. Some people use stocks/shares to replace the diamond ring because that they are more value for money.