I don't use the words becoming or attracting or anything like that in affirmations
I think this is all just semantics. It is not what you say, but what you believe that counts. You can say it however you like. The rest is just playing with words. You either believe something or you don't. It's that simple.
All you have to do is genuinely believe that it is possible to get to where you want to go. If you can't get yourself to believe that you can reach your target, then you gotta question what belief or beliefs are holding you back.
I wouldn't pay too much attention to the "here and now" concept. All it is meant to do is to get you to take action and focus on your goal in the NOW. Not tomorrow, not next week, not next year. Do it NOW! There is no better time. You wanna lose weight? Exercise NOW! You want to learn how to play the piano? Start practicing NOW!
Beyond this, it will only cause you to fool yourself, and you won't believe it anyway... If you say "I am getting healthy and rich now", but not do anything about it, you'll wait a LONG time to get healthy and rich.
Achieving goals does take time, and it will happen in the future if you don't already have it now. But the idea is to get going NOW instead of waiting for something to happen in the future. Will you ever get there? Will that future ever manifest? Time will tell...