As long as you just have stock injectors, you don't need an intercooler regardless of what chip you have. Unless you have a Cali truck you're only spraying 90cc of fuel, which isn't enough to cause the need for an I/C.
A couple (unsolicited) words of advice though; 1 -- ditch that K&N and get a 6637 kit. You can get them from Riffraff Diesel (as a kit) or build your own with a filter you can get at NAPA. 2 -- You can't really get a "bigger" chip. What you can do is get a chip that tunes that are burned for the configuration of your truck specifically. Look for a TS 6 position chip from PHP, TDP, or similar or a chip from DP Tuner. Do not, I repeat, DO NOT bother with a product from EDGE. They spend a lot of money on advertising, money that they refuse to pay when their programmer ruins your PCM.
Aside from that, yes the IC is a good upgrade if and when you decide to upgrade to bigger injectors, but until then, you're likely alright. The only way to know for sure is to install a set of gauges and watch the EGTs with your chip. Installing the gauges should really be the step just before installing a chip anyway. You need to keep an eye on things so you don't end up ruining something.
Again, welcome to the site. Hang around here and we will gladly suggest dozens of ways for you to spend all your $$!