Hi, thanks Brex, MajorD, and Dragonhydra for your ideas.
Major d, i like the extruded back part of your tricorder design, and the location of the isolinear chip, ive added it to the current tricorder design, aswell as the emergency button location.
I'm tickled pink by the way this is going.

If the isolinear chip can go all the way in, flush with the device, I was thinking pressing the chip in slightly would release a spring that would push it part way out so it can be pulled out the rest of the way. That way, you could have a chip in there the whole time without getting in the way. However, if the intent is to only ever have a chip temporarily, then only being able to go in part way makes sense.
On the matter of isolinear chips, I would love to see ones of various sizes.
http://www.treksinscifi.com/collection/thumbnails.php?album=41For the medical version what about bulking up the part around the removable scanner so it protrudes both up and out a bit as if the scanner were thicker than the thickness of the unit? But, the scanner doesn't need to be that thick, only look that thick when in the tricorder, or it can actually be that thick.
Which brings me onto the next point:
Having programs stored on iso chips doesn't make sense, as we know information can be transmitted wirelessly in a split second, and that tricorders for emergency purposes probably contain every program and utility they will ever need. (with the exception of the medical tricorder) So perhaps iso-chips should only be used by starfleet for high security missions, which for security purposes hasnt been downloaded or sent through the ship systems. Or other high security stuff?
Dragonhydra, i like your idea about being able to arrange the tabs and functions the way the player wants. perhaps this could be linked in with the idea of having isolinear presets, load in a iso-chip, and the associated tabs and options are automatically arranged to the top/ front.
You're right about the wireless aspect, at the same time it needs to be heavily exploited. I would go so far as always having a link to any open sensors. That way, if the ship is in range to scan and send pertinent data, it should automatically be integrated into the data you receive through the tricorder. It would explain how a tricorder can scan to a planet's core from the surface. However, since the tricorder is closer to the object or phenomena being studied, the tricorder should allow high resolution data within its range, leaving ship's sensors for long range, lower detail scanning. It's relative though, since ship sensors in Star Trek can read DNA from orbit, at least in a general manner.
I like the idea for isolinear chips. It makes sense for high security data transfer but it also makes sense for transferring extremely large files in a very short time due to high priority. There was an experiment done where a DVD was attached to a snail, and the snail's speed was measured. Snail pulled DVD's have a higher bandwidth than average broadband! As long as storage mediums outpace connection standards, physical data transfer should remain faster. There may also be programs large enough that they require an entire chip. I think Quark had two security programs on two separate isolinear rods to pass a high level security clearance, or maybe it was a single program but still on two rods.
I like the preset idea too. With a USB drive you can save all your settings for a computer, or even have a light OS build. Carrying around such an isolinear chip would allow you to save the interface preferences for multiple systems. Although, if you store your presets on your ship's systems, then retrieving those presets should be as simple as connecting to the ship. You would only need your presets chip if taking a trip where multiple transfers would be needed, such as going on an intervening shuttle ride and losing contact with your ship.
A personal collection of chips would probably involve high volume programs (such as holonovels), nostalgic data, secure personal information, secure work files, and general backups for those mindful of such things. There are color coded chips, so it's probably standard practice to divide such files among the appropriately labeled chips, which is a good idea in order to avoid losing everything thanks to the destruction of a single chip. An additional use for the tricorder could be as a wireless isolinear chip drive for when you don't have a convenient console with a slot.