This is the core Base structure. From it you can not only check your city Defenses and active Boosters, but also use some if needed. Additionally when upgrading your Headquarters you are able to unlock new Add-on slots, District Improvements and increase your base building speed permanently.

Headquaters Total Benefits

Lv.	Required Building(s)		Power	Gather Speed	Build Speed	Add-ons	Force
1	-	-	1 000	5	-	-	2
2	Army Command 1	-	1 000	10	-	-	5
3	Wall 2	-	1 050	10	1	-	17
4	Wall 3	Logistics Hub 3	1 050	15	1	-	49
5	Wall 4	Hydroelectric Station 4	1 050	20	1	-	125
6	Wall 5	Assembly Grounds 5	1 050	20	2	-	281
7	Wall 6	Civil Center 6	1 050	24	2	-	561
8	Wall 7	Hydroelectric Station 7	1 050	28	2	1	989
9	Wall 8	Embassy 8	1 050	28	3	1	1 518
10	Wall 9	Science Camp 9	1 050	32	3	1	2 131
11	Wall 10	Tech Development 10	1 050	36	3	1	2 804
12	Wall 11	Army Command 11	1 050	36	4	2	3 510
13	Wall 12	Logistics Hub 12	1 050	39	4	2	4 223
14	Wall 13	Assembly Grounds 13	1 050	42	4	2	4 960
15	Wall 14	Civil Center 14	1 050	42	5	3	5 860
16	Wall 15	Embassy 15	1 050	45	5	4	6 944
17	Wall 16	Science Camp 16	1 050	46	5	4	8 250
18	Wall 17	Tech Development 17	1 050	47	6	4	9 824
19	Wall 18	Hydroelectric Station 18	1 050	48	6	5	11 722
20	Wall 19	Army Command 19	1 050	49	6	5	13 998
21	Wall 20	Logistics Hub 20	1 050	50	7	5	16 732
22	Wall 21	Civil Center 21	1 050	51	7	6	20 031
23	Wall 22	Assembly Grounds 22	1 050	52	7	6	24 020
24	Wall 23	Science Camp 23	1 050	53	8	7	28 845
25	Wall 24	Embassy 24	1 050	54	8	7	34 681
26	Wall 25	Tech Development 25	1 050	55	8	7	41 748
27	Wall 26	Hydroelectric Station 26	1 050	56	9	7	50 314
28	Wall 27	Army Command 27	1 050	57	9	7	60 704
29	Wall 28	Logistics Hub 28	1 050	58	9	7	73 262
30	Wall 29	Assembly Grounds 29	1 050	60	10	7	88 505
31	Wall 30	Science Camp 30	1 050	62	10	7	105 641
32	Wall 31	Civil Center 31	1 050	64	10	7	124 920
33	Wall 32	Assembly Grounds 32	1 050	66	10	7	146 802
34	Wall 33	Army Command 33	1 050	68	10	7	171 628
35	Wall 34	Logistics Hub 34	1 050	70	10	7	199 756
36	Wall 35	Airfield 35	1 050	72	10	7	238 058
37	Wall 36	Warehouse 36	1 050	74	10	7	275 257
38	Wall 37	Civil Center 37	1 050	76	10	7	317 478
39	Wall 38	Embassy 38	1 050	78	10	7	365 100
40	Wall 39	Science Camp 39	1 050	80	10	7	418 769
41	Wall 40	Tech Development 40	1 050	82	10	7	478 653
42	Wall 41	Assembly Grounds 41	1 050	84	10	7	545 665
43	Wall 42	Army Command 42	1 050	86	10	7	620 421
44	Wall 43	Logistics Hub 43	1 050	88	10	7	704 178
45	Wall 44	Hydroelectric Station 44	1 050	90	10	7	799 242

HQ Level Up Rewards

Lv.	Gold Reward		Item Reward(s)
1		10 Gold		Extra Build Queue 24h
2		25 Gold		10m Speed Ups
3		50 Gold		Peace Shield 24h
4		75 Gold		Science Points Boost 8h
5		100 Gold		15m Speed Ups
6		200 Gold		200 Nano Materials
7		300 Gold		Peace Shield 3d
8		400 Gold		Extra Build Queue 24h
9		500 Gold		25m Speed Ups
10		600 Gold		All Resource Boost 1d
				Tempered Steel (Crafting Part)
				Rubber (Crafting Part)
11		700 Gold		Satelite Jammer 1d
12		800 Gold		500 Nano Materials
13		900 Gold
14		1 000 Gold		Gather Speed Boost 1d
15		1 150 Gold
16		1 300 Gold		25m Speed Ups
17		1 450 Gold
18		1 600 Gold		Peace Shields 6d
19		1 750 Gold
20		1 900 Gold		Science Points Boost 1d
21		2 050 Gold
22		2 200 Gold		50m Speed Ups
23		2 350 Gold
24		2 500 Gold		General Skill Reset
25		2 650 Gold
26		2 800 Gold		1k Nano Materials
27		2 950 Gold
28		3 100 Gold		1h40m Speed Ups
29		3 250 Gold
30		3 400 Gold		All Resource Boost 5d
31		3 550 Gold
32		3 700 Gold
33		3 850 Gold
34		4 000 Gold
35		4 000 Gold
36		5 000 Gold
37		6 000 Gold
38		8 000 Gold
39		8 000 Gold
40		9 000 Gold
41		9 000 Gold
42		10 000 Gold
43		10 000 Gold
44		12 000 Gold
45		12 000 Gold