The coinbase value in GetBlockTemplate is the coinbase value which will be used in the coinbase transaction of the produced block. As such it includes the sum of transaction fees plus the current subsidy (25 BTC at the time of writing).

If building the coinbase by hand one thing to consider is that the coinbase check in Bitcoin is "loose". For a block to be valid, the value of the coinbase can not be more than the computed subsidy plus transaction fees. It can however be any smaller value including zero. This was likely an oversight by Satoshi but it has led to some blocks being minted with a smaller than allowed coinbase. This results in coins being permanently destroyed.

Judging from the output of a GBT call to bitcoind (2505616072), it must include fees.