I have been learning Chữ Nôm on and off for just over a year now and have accumulated at least 1000 characters. I use Chữ Nôm to practise writing all my Vietnamese articles, short stories and poems etc. From the lists you have presented, I have learnt each of those characters but I also use alternatives or even my own invented characters (especially for characters that didn't exist).
For the numbers, I just revert to the simple Chinese characters 一二三... since the sino-Vietnamese numbers are often relegated to other uses.
For the word là, I use 羅.
For the word tôi, I replace the stone radical with a man radical.
For the word khoẻ, I use 劸.
1 thing I find absolutely fascinating about Chinese characters is how they are adapted to other languages especially to the CJKV languages. The Japanese not only borrowed Chinese characters, they even created their own Hanzi and their two syllabaries Hiragana and Katakana from Chinese characters. The Koreans also used systems of writing such as Idu and to some extent use Chinese characters for distinguishing between homophones, but mostly now use Hangeul which although looks nothing like Hanzi, you can see the influence in the way the syllable stacks into a block. Vietnamese is the odd one out since it completely turned its back on characters preferring a Romanisation of the language instead of using Chữ Nôm.
There are only a few thousand people in the world who can read and write Chữ Nôm to a decent extent, even fewer who can fluently utilise it. There are, however, numerous organisations dedicated to preserving the script which was never truly standardised and only officially used for 14 years during the Tây Sơn (西山) Dynasty. I am fortunate enough to have a multitude of resources from which to learn Chữ Nôm. There are even plans to start teaching Chữ Nôm as part of overseas Vietnamese studies curricula and plans to introduce a Chữ Nôm curriculum in Vietnam itself. I think that this would be a great idea since it would not only NOT affect the usage of Chữ Quốc Ngữ as the official script, but it would allow younger generations of Vietnamese to have a tangible link to their forefathers. In the process, it would mean that more people would have knowledge of Chinese characters.
I just ordered a complete Chữ Nôm dictionary a few days ago called "The Dictionary of Nôm Characters with Excerpts" (Tự Điển Chữ Nôm Trích Dẫn). It costs $75 + $25 P&H ($USD100) so it's probably the most expensive publication that I've ever bought!
Tự điển in trên giấy đẹp, tốt, trình bày mỹ thuật, bìa cứng, với hơn 1700 trang, và có trên mười ngàn mục từ với trích dẫn phong phú và giải thích cách cấu tạo chữ rõ ràng.
"The dictionary is printed upon paper that is beautiful, of good quality, with a beautiful layout, hardcover, with over 1700 pages, and over ten thousand entries with an abundance of excerpts and clear explanations of how to properly use the word(s)."
Oh boy! I'm probably gonna go blind soon! Anyway, I believe that the Chữ Nôm script was and is an invaluable source of historical and cultural significance to the Vietnamese. I believe that had it not been for the romanisation of Vietnamese by the European missionaries, that a form of Chữ Nôm would probably have still been used to this very day. Also, it was the first official script (albeit officially used for just 14 years) that the Vietnamese themselves created to express their native tongue.
I mean, if the elites had been educated in Classical Chinese for years and years, then why not just stick to the Classical Chinese language? Why even bother creating Chữ Nôm at all? And sure Chữ Nôm looks like a cheap copy of Chinese, but wasn't the Chinese script all the elites were known to have used? Had they been exposed to other scripts of the world, who knows what type of script Vietnamese people would be using, or even if we would be calling them Vietnamese at all?