Cloaking tech isn't that scary, there are actually pretty sound reasons to get into the field:
For one it makes it much harder for belligerent powers to get a read on the Federations total ship strength, that uncertainty means that provoking or pressuring the Federation is now much riskier, which makes them more amendable to listening to our diplomats.
For another, it makes it much harder for powers like Cardassia to engage in covert operation since now they have to worry about cloaked ships tailing their vessels through the border zone or even having cloaked vessels encroach into the Cardasssian interior to gather SIGINT.
Thirdly - MAN THINK OF THE SCIENCE! We're talking about using precisely calibrated subspace fields to refract, reflect and bend broad parts of the electromagnetic spectrum into a pretzel. The improvements we could make to our sensor technology! The sheer cool factor of developing the technology!
Mostly, cloaking tech raises the cost of doing business with respect to messing around with the Federation. Now peer powers who don't like us have to spend resources on vast tachyon detection nets and sensor technology - resources they can no longer use for other things like building ships or financing covert ops against us.