In my case, i go for component speakers first. Then later go for change HU. I believe if the HU signal stronger but OEM speakers cannot assist in output.

Yeah... that's what it means.

2-ways component speakers is made up of 2 6.5" bigger speakers + 2 smaller speakers (aka tweeters) + 2 units small box (crossovers)

3-way component speakers is normally made up of 2 6.5" bigger speakers + 2 4" medium size speakers and 2 small size tweeters + 2 units box (crossovers)

Yeah.. I agree wtih zennn, change speakers first