Normally, general tips come naturally. And if you're going to Hard Mode, then the general tips that you obtained from playing through and 1cc'ing Normal should be enough to pull you through most situations. If not, then they'll pick up quite quickly.
For the most part, I can't do well with bullets that criss cross diagonally. I imagine Apollo 13 would be the best spellcard to practice that, wouldn't it?
Any Spell Card or Attack Phases that crisscrosses (such as the one you pointed out) is great for practice. Although, I don't believe enough people actually know the general tip for dealing with this.
Personally, I try to look at the crisscrossing as "two halves". I follow this routine. Of course, a quick mind is always handy.
1. (quickly) Analyze one half of incoming pattern (usually bullets incoming from the left side).
2. Position self accordingly to the least dense area.
3. Analyze the other half of incoming pattern.
By this time, I would be inside the pattern.
4. Micrododge, focusing more on the bullets from the "other half".
Not sure if that will help though.