In MMP, you need to quickly alternate normal shot and lard attacks to build your medals quickly. At the start of stage 1, after you kill the first two waves of enemies and power up once (thus enabling the lard attack), try to hit only one or two enemies with the lard attack and get the 100 pt medal from them. After you absorb those medals, the next medals you get will be worth 200 pts. So kill another popcorn enemy with the normal shot, grab the pig to get a tiny amount of power, and use the lard attack on another popcorn enemy and absorb their medals. Then you just quickly repeat that as fast as you can until you get up to the max of 10,000. I usually have my medals maxed by the first mid-boss.
You don't stay at 10,000 forever though. If you let a medal fall off screen, it'll knock their value back down to 1000 pts. But that's not necessarily true - you can let medals drop off screen IF you are in the middle of a lard attack. So if there's a huuuuge wave of enemies coming up, you can just hold the lard down the entire time and let a bunch of medals fall off screen. As long as you survive and absorb the remaining medals, you'll still be at 10,000.
I don't really know anything about Pink Sweets, so I can't help much there. I need to research it a little more before I really dive into it. And I haven't even tried either arrange mode besides the MMP Matsuri version.
Also, take note: the guides on shmups/cave-stg are for the arcade versions of MMP and PS. The 360 port defaults to version 1.01 for both games (the arcade games are version 1.00). The MMP guide still works pretty well since there isn't much difference between the modes, but as far as I know, there are quite a few differences in Pink Sweets. So a lot of the stuff in the guide probably won't apply to it.
Playing MMP solely for survival is a little tricky, I think. If you have 3-5 lives in stock, the rank progresses faster, so you need to suicide when you're doing well to keep things from getting too crazy. Personally, I haven't bothered doing that yet since I constantly die to stupid shit (running into random bullets, crashing into enemies, etc) so I need all the lives I can get.