I really couldn't grasp the first part of your post, i understand that you are proposing that we prioritize our bitcoin investment but that in no way should be out of our disposable income, whether you like it or not our daily needs comes first before investing in Bitcoin and the best we can is to limit some of out extra expenses to get our discretionary income up and invest in bitcoin.
A disposable income doesn't or in no way is the left over of our income, its rather what is left after all our expense has been removed, and with that amount we can chose to invest it in bitcoin, you can't be insinuating that we put bitcoin investment first and then take what is left for expense, we woudl surely regret that cause we can get into unnecessary debt or emergencies due to such poor cashfkow management decision, so it's always going to be better toninvest out of our discretionary income.
Actually, in planning the investment you want to make, it is better to focus on your monthly income, where you can budget 10% or 15% for buying Bitcoin, isn't that simpler to understand. Apart from that, don't complicate the situation where you have to take a loan to invest in bitcoin because that is not a very good action. Therefore, invest as much as you can. If you can afford to buy Bitcoin with $20 per week, then apply it every week.
Well, if the points you convey are of course correct, but sometimes your monthly spending needs increase and will you miss purchases that month? Now, in this case, it must be underlined that when investing in the long term, initial planning is of course required, which is a priority so that this will not interfere with spending on any monthly spending needs.
In essence, people who invest are those who want to change their fate in the next decades, therefore they need to develop a wise strategy so that their investment can run smoothly. Accumulating regularly every week is a pretty brilliant idea and also increasing the budget to buy aggressively is the second option in long-term planning. But you can organize each strategy neatly and can also go hand in hand with a new strategy by acting aggressively when prices drop and also buying in a lump sum to increase BTC holdings.