The Federation, Klingons, and Kzintis do have battle pods equipped with drone racks. But there is a difference between the number of drones one can keep in storage on the one hand, and the amount which can be loaded into a ship's (or base's or battle pod's) drone racks during the course of a given scenario on the other.
-----
Actually, I should probably take this opportunity to go into more detail on how the SFU handles the concept of tugs and transports.
Another of the legacies of the
Star Fleet Technical Manual embraced by the Star Fleet Universe is
the Ptolemy-class tug.
As shown of the cover of
Federation Commander: Transports Attacked, the Klingons have fleet tugs of their own:
However, while the Federation TG and the
Klingon T7 might be among the most prominent of Alpha Octant fleet transport designs, not every empire was able to go about things the same way - be it in terms of the hulls used to do the transporting, or in the type of missions said transports were to be sent on.
-----
In engineering terms, the key to a tug is the "bracing" needed to carry
one or
more pods. Pods can be either "single-weight" or "double-weight" types; the Move Cost and Turn Mode of the tug are reduced depending on the number of "pod-weights" being carried.
Back in the Early Years, the forerunner of the "Franz Joseph" tug was a Y-era tug - one of the first generation of Federation ships designed from the keel up to serve the needs of a unified Star Fleet.
At the time, tugs were mainly used to transport either bulk cargo (for civilian and/or military use) or passengers (in "starliner" pods). In peacetime, these ships were used to help found new colonies and to support the construction of new deep-range bases. In wartime, they could be used to ferry supplies to the front, and to rotate officers and crewbeings into and out of service.
Notably, over in the Inter-Stellar Concordium (which had yet to make First Contact with the other Alpha empires in this time period), their "two-prong" early tug was designed to carry either two pods or none; they were unable to carry only a single pod. As for the Early Years Paravians, who (mostly) refused to establish bases or colonies outside of heir home system, their tugs were used mainly to support long-range raids into Gorn space. And while the M81 Pirates used ships that were
de facto tugs (ones intended to cart off entire freighters!), the Tholians themselves had not built fleet tugs back in the home galaxy; the best the early Holdfast could manage was
a cargo variant of the patrol corvette.
-----
In the Middle Years, the first "modern" tugs began to emerge, such as the
Ptolemy-class itself. This era also saw changes in how these tugs were being used.
On the one hand, new pod types started to emerge. This included battle pods (which turned a "
battle tug" into a powerful, if slow, warship) and self-defence pods (which offered an increased measure of protection but with a reduced cargo capacity). As fighters became more prevalent across the Alpha Octant,
carrier pods started to emerge also, as did gunboat tender pods later in the General War.
On the other hand, the development of the
mobile base greatly changed the manner by which a given empire could build new bases (or replace lost ones) - not least since tugs could be assigned to aid in the transporting, unpacking, and later upgrading of these bases into larger and more powerful base types.
Once again,
the "modern" ISC tug was obliged to carry two pods at a time, or none at all. For their part, the Lyrans designed their survey cruiser to double as a fleet tug (
or perhaps as a carrier tug), so as to better support operations in the "off-map" Far Stars region. The Lyrans, like a number of other Klingon-allied (or at least Klingon-adjacent) empires, designed their tugs to be able to carry Klingon-type pods as well as their own pod or pallet types.
Also, the "lost empire" Paravians (would have) built dreadnought-sized
Raid Motherships; unlike heavy cruiser-sized fleet tugs, these ships were (or would have been) able to carry as many as three pod-weights' worth with no reduction in Move Cost or Turn Mode. There is even a conjectural Battleship Raid Mothership in
SFB Module C6 which can carry as many as
four pod-weights, again with no Move Cost or Turn Mode penalties!
On the other end of the scale, several empires were able to develop transport variants of their frigate and/or destroyer hulls, though they were much more limited in terms of how many pods they could carry (basically one) and what variant pods they could operate (no "battle frigate transports", for example).
-----
As the General War loomed, the onset of "wartime construction" hulls such as the Federation NCL and the Klingon D5 led to the emergence of the light tactical transport: a war cruiser variant with some, but not quite all, of the capabilities of a full-sized fleet tug.
Notably, the Klingons designed both their
D5H transport and D5G commando ship to operate as LTTs, so that the latter could leverage the use of commando pods to further support planetary invasions.
As for the Romulans, who were otherwise obliged to built less capable
Freight Eagles, or to import a Klingon tug
to convert into a Romulan KRT, the
SparrowHawk-T provided the Empire with a "home-grown" transport option - but only after they conceded that the
SparrowHawk-H (which could not carry pods) was not going to suffice for the task at hand.
As for the ISC, their battle pods were designed to be used in pairs by the fleet tug. So they had to develop a separate light battle pod which could be used by itself
on their LTT.
-----
Combined with a series of logistical advances which made supply lines longer and mobile bases quicker to install, the new range of tugs, LTTs, and other transports made the rapid advances of the General War possible.
The ISC went one further, refining the pre-fabricated pacification bases and rapid deployment procedures that make their post-war intervention possible.
Later on, as the surviving Alpha empires steadily turned the tide against the Andromedan invaders, the combination of tug (or LTT) and mobile base would enable the launch of a campaign which would change the course of Star Fleet Universe history:
Operation Unity.