Maybe.  I usually have 1 or 2 set at 6th-7th inning because I don't want to blow thru my entire bullpen in any given game.    Sometimes I have all at "any".   But, when attempting to convince someone of the virtues of not using a closer, I have to tell them "7th-8th" inning because they beleive that they have to have their best RP pitching last. 

I had a couple of long relievers go on the 15 Day DL.  Brought up guys from AAA.  Now the guys from AAA are holding their own in middle relief so far, we're in midseason, and I wouldn't mind giving the new guys a longer look.  Can I just leave the DL guys there until I feel like taking them off?  Will there be any drag on their ratings if I do?

You can leave them there.   No harm will come if they're veterans.   If they're still developing, they might miss the playing time.

On my phone so I can't link, but how many innings can I get out this guy? What would you put his pitch count at?

http://whatif.cincinatti.com/HBD/Pages/Popups/PlayerProfile.aspx?pid=5272394

120-150 per year depending on effectiveness in your world.    I'd set him at 55/70 and adjust if he was missing his start with 92(100) or something like that

What is the deciding factor for which team gets the higher pick when a team signs multiple type A free agents?

One of my worlds just rolled over, but we haven't filled yet. In this world, I have an ace pitcher that is a free agent, and I'd like to re-sign him. Last season I couldn't make him an offer. The text in the offer screen said he wanted to test free agency, and it didn't allow me to submit any offers.

Now, the offer screen just says his primary concern at this point in his career is to make the playoffs. It doesn't say anything about wanting to hit the market.

Does this mean I'll be able to re-sign him before free agency starts?

No.   Odds are he won't.    Unless, of course, his ratings declined.

Are type-A free agents able to be signed without losing a draft pick once the season starts? There are a few in my world that are decent but I don't think anyone will sign them and lose the pick.
If so at what point?

Type A designation drops when you can see potential draftees.

how long after the final w.s. game do the credits show up?

I've never had them show up any later than next day.  But WifS is doing some sort of purchasing update so there might be a monkey wrench thrown in there.

how much does a brutha get for not making the playoffs?

$4 for 4th, $1 for 3rd and I don't think you get anything for 2nd if you miss the playoffs.