The design is practically finished, but I thought it would be cool to post it in here as well 
The Haydens, under the direct supervision of Starfleet's Centre for Stellar Cartagrophy, or SC², usually venture off of known shipping lanes, tend to avoid making first contacts as much as possible (leaving that sort diplomatic tasks to a ship of the line), and are fast. Their sensor-packed pods are directly connected to the nacelles and as a result feed off of them, making them very powerful. The ships are not unarmed but if they ever find themselves in a fight their main rescue is their sheer speed. They are slightly faster than an Intrepid class, but use a Defiance line core to gain that speed, which also brings some of its negative aspects with it. The pods also create a considerable subspace drag but Starfleet Command found the design elegant and small enough to justify this.
Outside of the shipping lanes things can get a little rough, though, especially when there are people operating there who don't want others to know what they're up to, like the Orion Syndicate. To counter that threat, Haydens have the latest ablative armor generators installed, deploying a 3cm thick shell when needed; this has helped in more than one occasion to get a Hayden out of trouble and back to the relative safety of a space station or friendly territory. Data collection is the most important task these ships have and they intend to return that precious data back to the Federation; they return to a data station, where they transfer off the collected data and where it gets transmitted using a highly encrypted subspace link. The ships themselves don't have the capability to send such a message as it would make them even more valuable for enemies of the Federation than they already are...
It is rumored that Section 31 uses an adapted version of the Hayden, complete with a cloaking device, but this hasn't been confirmed. During a crossover to an alternative universe it was discovered that this version of the Terran Empire used an almost similar design with a similar name; however, it was used for spying on the subjects of the Empire instead of the nobler cause our own Hayden supports.
In this recorded image, the USS Hayden has encountered an old and abandoned Leopard class frigate, without a name or registry number...
The Haydens, under the direct supervision of Starfleet's Centre for Stellar Cartagrophy, or SC², usually venture off of known shipping lanes, tend to avoid making first contacts as much as possible (leaving that sort diplomatic tasks to a ship of the line), and are fast. Their sensor-packed pods are directly connected to the nacelles and as a result feed off of them, making them very powerful. The ships are not unarmed but if they ever find themselves in a fight their main rescue is their sheer speed. They are slightly faster than an Intrepid class, but use a Defiance line core to gain that speed, which also brings some of its negative aspects with it. The pods also create a considerable subspace drag but Starfleet Command found the design elegant and small enough to justify this.
Outside of the shipping lanes things can get a little rough, though, especially when there are people operating there who don't want others to know what they're up to, like the Orion Syndicate. To counter that threat, Haydens have the latest ablative armor generators installed, deploying a 3cm thick shell when needed; this has helped in more than one occasion to get a Hayden out of trouble and back to the relative safety of a space station or friendly territory. Data collection is the most important task these ships have and they intend to return that precious data back to the Federation; they return to a data station, where they transfer off the collected data and where it gets transmitted using a highly encrypted subspace link. The ships themselves don't have the capability to send such a message as it would make them even more valuable for enemies of the Federation than they already are...
It is rumored that Section 31 uses an adapted version of the Hayden, complete with a cloaking device, but this hasn't been confirmed. During a crossover to an alternative universe it was discovered that this version of the Terran Empire used an almost similar design with a similar name; however, it was used for spying on the subjects of the Empire instead of the nobler cause our own Hayden supports.
In this recorded image, the USS Hayden has encountered an old and abandoned Leopard class frigate, without a name or registry number...
I have someone who makes my treknobabble and he said that the big impulse engines are good 
I would have liked to have seen that on screen!
