だけに details

write + all the more so

kaku dake ni

all the more so; given how much X — the extent of the reason sets the size of the result

地元じもとのチームだけに、負まけたときのショックがでかい。

jimoto no chiimu dake ni, maketa toki no shokku ga dekai.

It being the home team, the sting of a loss is that much worse. casual

今回こんかいは準備じゅんびに時間じかんをかけただけに、結果けっかが出でなかったのは悔くやしい。

konkai wa junbi ni jikan o kaketa dake ni, kekka ga denakatta no wa kuyashii.

Having put so much time into preparing this time, coming away with nothing stings all the more. neutral

Examples

all the more so — the reason is weighed, and the result lands with a force to match

地元じもとのチームだけに、負まけたときのショックがでかい。

jimoto no chiimu dake ni, maketa toki no shokku ga dekai.

It being the home team, the sting of a loss is that much worse. casual

今回こんかいは準備じゅんびに時間じかんをかけただけに、結果けっかが出でなかったのは悔くやしい。

konkai wa junbi ni jikan o kaketa dake ni, kekka ga denakatta no wa kuyashii.

Having put so much time into preparing this time, coming away with nothing stings all the more. neutral

彼かれは現場げんばを長ながく見みてきただけに、説明せつめいが具体的ぐたいてきだ。

kare wa genba o nagaku mite kita dake ni, setsumei ga gutaiteki da.

Precisely because he has spent years on the floor, his explanations are concrete. neutral

長年ながねん取引とりひきのある会社かいしゃだけに、今回こんかいのご判断はんだんは残念ざんねんでなりません。

naganen torihiki no aru kaisha dake ni, konkai no go handan wa zannen de narimasen.

Coming from a company we have dealt with for so many years, this decision is all the more disappointing. formal

The main clause often carries よけいに／なおさら／一層いっそう, which is
the proportion showing on the surface. Unlike だけあって it is free to end
in disappointment.

だけあって
だけあって passes a verdict, always favourable, that the result MATCHES what X promised (さすがプロだけあって速はやい); だけに commits to no valence and takes an unwelcome result freely — 期待きたいしていただけにがっかりした is ordinary, while ×期待していただけあってがっかりした is not.
ので
ので gives a reason as flat circumstance and says nothing about how much of it there was; だけに reads the reason as a QUANTITY and makes the result follow in proportion, so an intensifier (よけいに, なおさら, 一層いっそう) stands unaided in its main clause where after ので it needs earlier context to lean on.
からこそ
だけに weighs the reason as an amount and makes the result follow in proportion to it; からこそ weighs nothing and only rules the rival causes out, so its main clause reaches for an explanatory のだ that names this reason as the account (難むずかしいからこそ、やる価値かちがあるんだ).

だけ
The same だけ, and the に flips the reading — 好すきなだけ食たべる limits an amount ("eat as much as you like"), while 好すきなだけに reasons from the extent of it ("precisely because he likes it"); a learner who hears "only" in だけに gets the sentence backwards.