General

Time your genesis and use when there are really big mobs to clear them quickly.
Spam Big Bang and try to keep the mobs packed closely together, don't let them stray too far.
Use Angel Ray for range to save time spent actually travelling to the mob to use Big Bang.

I had 200 k at the time so I flew through

I was able to solo it fine, but I will admit, it's a lot less stressful on a more attack focus job (like BM). Just time your Genesis'... Righteously Indignant helps a lot. You may just need to upgrade your range.

Dude... forget just fighting in DiPQ... I solo DiPQ. I have yet to find a character that is unable to solo DiPQ (though I haven't tried it with everyone... methinks Mihile as he currently is wouldn't be able to). My Bishop is no exception to this. You just need to use your skills, mob with Gen+BB and maybe use Teleport Mastery to telecast for that little extra damage. The only real challenge ought to be the obelisk at the end, but in that case, use Infinity and unload your best damaging attack on it.

Also, use Holy Magic Shield when you can.

Genesis Big Bang typicly does it, and if it doesn't work - then you should improve your DPS by getting better equips.
Meanwhile you can party with 1 other member (duo) to improve EXP and PQ efficiency.

Use AR when you need range and big bang (on Gene CD) to clear out tightly packed mobs

DIPQing as a Bishop wasn't too hard for me. I would just find a party, Genesis and spam Big Bang. It would pretty much clear extremely fast.

Duo with 1 more person. They'll want you for HS.

Do you even lift?
If not, find a party.

well getting guud is something
but usually i just use that ray thing and big bang and sometimes holy arrow on the bosses